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Effect of fiber entanglement in chopped glass fiber reinforced composite manufactured via long fiber spray-up molding. Heliyon 2023; 9:e22170. [PMID: 38213576 PMCID: PMC10782114 DOI: 10.1016/j.heliyon.2023.e22170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 10/27/2023] [Accepted: 11/06/2023] [Indexed: 01/13/2024] Open
Abstract
Long Fiber Spray-up Molding (LFSM) deviates from the conventional approach in liquid composite molding (LCM) processes by utilizing extremely long chopped strands of fibers as the primary reinforcement material in its fabrication process. In LFSM, chopped fibers are impregnated with resin that is sprayed vertically downwards before reaching the mold surface. The spraying mechanism is mounted on an actuator, which is capable of spraying freely in any specified pattern or direction. Under LFSM, it is extremely difficult to fabricate a composite part with uniformly distributed fiber content throughout its volume. The consequences of the non-uniform fiber volume distribution arise from the fiber entanglement as the length of the fiber reaches up to 100 mm in LFSM. In this study, the effect of fiber entanglement during LFSM was analyzed through various approaches. This included measuring the coefficient of friction between fibers in contact and examining the correlation between fiber lengths and the number of intersections. Furthermore, the viscoelastic properties of the uncured composite part were assessed by experimenting with the influence of viscosity on fiber length during compression molding. The results were then computed, modeled, and visualized in MATLAB, considering variations in viscosity and fiber length, both before and after compression molding.
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Correlation of haemophagocytosis with clinical criteria of haemophagocytic lymphohistiocytosis and recommendations for bone marrow reporting. Pathology 2021; 54:434-441. [PMID: 34711415 DOI: 10.1016/j.pathol.2021.07.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 07/18/2021] [Accepted: 07/28/2021] [Indexed: 10/20/2022]
Abstract
Haemophagocytic lymphohistiocytosis (HLH) is a rare condition resulting from a dysregulated inflammatory response. Currently there are no guidelines on the reporting of haemophagocytosis on bone marrow biopsy (BM) and lack of evidence on correlation between haemophagocytosis with the clinical diagnostic criteria for HLH. We aimed to assess if the amount of haemophagocytosis identified in the BM correlates with HLH-2004 criteria. Secondary aims were to evaluate inter-observer variability in reporting haemophagocytosis, and to formulate recommendations for screening in bone marrow specimens. A retrospective review of bone marrow biopsies from adult patients under investigation for HLH was undertaken independently by two haematopathologists who were blinded to the original biopsy report. The average number of actively haemophagocytic cells in each slide were quantified. Cases with discordance pertaining to the degree of haemophagocytosis were reviewed by both assessors to reach a consensus. Sixty-two specimens from 59 patients were available for assessment. An underlying haematological condition was identified in 34 cases (58%). There was a significant association between the amount of haemophagocytosis identified on the aspirate samples and the number of HLH-2004 criteria met (p<0.0001). In patients where haemophagocytosis was present (n=31), there was a correlation between the amount of haemophagocytosis and ferritin (p=0.041). Based on our review, we have made recommendations for the reporting of BM haemophagocytosis. Our findings indicate that the amount of haemophagocytosis present on BM samples correlates with the number of HLH-2004 criteria. We found marked interobserver variability which we anticipate can be rectified with our recommendations for reporting.
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Effect of ammonium polyphosphate and acrylic acid on
NaCl
treated electrospun
PLA
microfiber mat. POLYM ENG SCI 2020. [DOI: 10.1002/pen.25483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Analysis of Cryogenic Impact Properties for a Glass-Fiber-Reinforced Dicyclopentadiene with a Different Amount of Decelerator Solution. MATERIALS 2019; 12:ma12193246. [PMID: 31590247 PMCID: PMC6804003 DOI: 10.3390/ma12193246] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 09/22/2019] [Accepted: 09/30/2019] [Indexed: 12/03/2022]
Abstract
Composites using dicyclopentadiene (DCPD) as a matrix have gained significant popularity owing to their excellent impact and chemical corrosion resistance. In the present study, experiments addressing the impact behavior of glass-fiber-reinforced DCPD were conducted to quantitatively evaluate its impact properties. The glass-fiber-reinforced polydicyclopentadiene composite utilized in impact tests was manufactured using structural reaction injection molding (S-RIM) because of its fast curing characteristics and low viscosity. The impact properties of the glass-fiber-reinforced DCPD (GF/DCPD) were quantitatively evaluated by varying its fiber content and decelerator solution. The impact properties of neat DCPD and GF/DCPD composites were examined with different amounts of decelerator solution under various temperatures from room temperature to cryogenic temperature to observe the ductile-to-brittle transition temperature (DBTT). With an increase in the fiber weight fraction of the GF/DCPD composite, the effect of the DBTT significantly decreased. However, the decreasing rate retarded as the weight fraction of the GF increased. The decreased DBTT with the addition of GF in the GF/DCPD can be attributed to the differences in the thermal expansion ratio and the interfacial force between neat DCPD and the fiber. A fractograph analysis demonstrates that the effect of the brittle (smooth) surface resulted in a lower impact absorbed energy when the temperature decreased, along with the increased amount of the decelerator.
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Preparation of solid-state micro- and nanocellular acrylonitrile-butadiene-styrene (ABS) foams using sub- and supercritical CO 2 as blowing agents. J Supercrit Fluids 2017. [DOI: 10.1016/j.supflu.2017.01.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Mechanical properties of norbornene-based silane treated glass fiber reinforced polydicyclopentadiene composites manufactured by the S-RIM process. E-POLYMERS 2017. [DOI: 10.1515/epoly-2016-0257] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractA lab scale structural reaction injection molding (S-RIM) piece of equipment was designed and used to fabricate glass fiber reinforced polydicyclopentadiene (p-DCPD) composites for three different fiber contents. In order to obtain information regarding the optimal process temperature (>80°C) and the curing time (<30 s), differential scanning calorimetry (DSC) was used to investigate the curing behavior of DCPD resin under isothermal conditions. Further, a norbornene-based silane treatment was used to improve the interfacial adhesion between the glass fibers and DCPD as confirmed by the micro-droplet pull-out test and scanning electron microscopy (SEM). Fabrication of glass fiber/p-DCPD composites with improved mechanical properties was carried out based on the optimized process conditions and surface treatment of glass fiber.
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Effect of a pressurized cavity on the replication of micro-patterns with injection molding. E-POLYMERS 2016. [DOI: 10.1515/epoly-2016-0061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractIn this investigation, we studied the effect of the cavity air pressure on the replication of micro-patterns in injection molding. When pressure is applied to the cavity air, the pressure at the flow front is also increased and thus the overall pressure gradient in the polymer melt is lowered. Therefore, the melt flow in the cavity becomes slower providing more time for the polymer melt to fill the patterns on the cavity surface resulting in the improvement of replication of the microscopic pattern. We carried out experiments for molds with a macroscopic pattern (ribs) and a microscopic pattern on the surface. In order to evaluate the quality of replication, we measured the filling heights of patterns with different ratio of the cavity air pressure to the injection pressure. The results showed that the application of cavity pressure helps the replication of patterns both for macroscopic and microscopic scales.
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Abstract
BACKGROUND Smoking is considered as a major modifiable risk factor for cardiovascular diseases. It has been shown that smoking cessation drops the risk of cardiovascular diseases such as myocardial infarction and also improves platelet function. Because mean platelet volume (MPV) is a simple and convenient indicator for platelet activation, we planned to investigate the effect of smoking status on MPV in healthy populations. METHODS This study was conducted on 398 individuals who visited our hospital for regular medical check-ups and were confirmed not to have diabetes or hypertension. MPV was measured using EDTA blood on an Advia 2120 (Siemens Healthcare Diagnostics Inc., Tarrytown, NY, USA) within 2 hours. RESULTS Present smokers showed higher MPV levels than present non-smokers. When MPV was compared by taking previous smoking history and present smoking status into account, the smoking cessation group showed significantly lower MPV levels than other groups. CONCLUSIONS Because this finding was significant only in the female group, the change in MPV according to smoking status was found to be different by gender. We carefully suggest that smoking cessation can lower the risk of cardiovascular diseases through the change in MPV, which can be more effective for women than men.
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Preparation of Waterborne Polyurethane-Acrylic Hybrid Solutions from Different Types of Acrylate Monomers. KOREAN CHEMICAL ENGINEERING RESEARCH 2012. [DOI: 10.9713/kcer.2012.50.3.410] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Self-organized anisotropic wrinkling of molecularly aligned liquid crystalline polymer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:3576-3582. [PMID: 22242834 DOI: 10.1021/la203799h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Anisotropic wrinkling which utilizes the anisotropic nature of liquid crystalline polymer (LCP) is demonstrated as a means of physical self-assembly to produce periodic microstructures. Through the plasma treatment on the molecularly aligned LCP film surface, one-dimensionally ordered wrinkle pattern was spontaneously formed on glass substrates without employing external thin-film deposition or prestrain control of the system. Experimental results indicate that the directionality of the wrinkle pattern can be tailored by the structural ordering of LCP molecules in the bilayer system of a hard skin layer on a soft substrate. Studies on process variables, such as the plasma treatment time and the film thickness, were conducted to figure out the effect on the wrinkling morphology. Due to its spatial periodicity over a large area and undemanding requirement of the process, this approach can be a candidate for the microfabrication in various applications.
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Safe and effective gene transfer by adeno-associated virus of neonatal thymus-derived mesenchymal stromal cells. Tissue Cell 2011; 43:108-14. [PMID: 21310455 DOI: 10.1016/j.tice.2010.12.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2010] [Accepted: 12/24/2010] [Indexed: 12/25/2022]
Abstract
Recently, human neonatal thymus-derived mesenchymal stromal cells (nTMSCs) have been recognized as a promising mesenchymal stem cell source for combined cell and gene therapy. While efficient gene transfer is crucial for optimizing therapeutic efficacy, almost no studies have yet reported on the characteristics of nTMSC in terms of genetic modification. The present study investigates and realizes the potential of self-complementary adeno-associated viruses (scAAVs) as an effective transduction tool for nTMSCs. Transduction efficiency (TE), cytotoxicity and functional characteristics were determined in nTMSCs isolated from thymic tissues and transduced with scAAV1-6 and -8 serotypes expressing GFP. Our study confirms MSC-typical characteristics in nTMSCs and additionally, suggests further therapeutic advantages of nTMSCs due to its particularities with lower levels of MHC class I protein and higher levels of CD31 and CD34 expression. Effective transduction by scAAV2 and scAAV5 was evident in the majority of nTMSCs that were GFP-positive at a multiplicity of infection (MOI) of 1000. TE was further improved by higher MOI treatments. Transduced cells also successfully maintained adipocyte and vessel-forming endothelial cell multi-potency and showed no evidence of gene delivery-related cytotoxicity. Collectively, the data strongly suggest that scAAVs are promising technical platforms for safe and effective transgene expression in nTMSCs.
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Contribution of TNF-α-308 gene polymorphisms to susceptibility to the development of uveitis in Korean patients with HLA-B27-positive ankylosing spondylitis. Scand J Rheumatol 2011; 40:317-8. [DOI: 10.3109/03009742.2011.569752] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Abstract
Of all patients with systemic lupus erythematosus (SLE), 15-20% are diagnosed during childhood, with disease onset prior to the age of 16 years. Because disease expression in SLE is influenced by environment factors and differs between racial and ethnic groups. The aims of this review were to describe prevalence, clinical manifestations, common infectious complications, and outcome of pediatric-onset SLE in Asia. The prevalence of pediatric-onset SLE was 6.3-19.3 per 100,000 in Asia. The ratio of female to male was 4.7-6.2. The mean age at diagnosis of pediatric-onset SLE was 8.6-13.5 years. The most common clinical features of pediatric-onset SLE in Asia were cutaneous rashes, arthritis, hematological involvement and nephritis. The occurrence of nephritis varies from 29% to 81%. The most common histopathology of lupus nephritis was diffuse proliferative glomerulonephritis (WHO Class-IV) which occurred in 39.4-54% of case of lupus nephritis. Pediatric-onset SLE patients with infections have poor outcomes than uninfected patients. Gram-negative bacilli are the most common microorganisms responsible for bacteremia in Asian patients with SLE. Recurrent major infections predict poorer disease outcome and associated organ damage in pediatric-onset SLE. Improving the survival of SLE patients was reported in Asia in recent decades. The survival was 92% at the age of 5 years, 86% at 10 years and 79% at 15 years in children with SLE in Taiwan in 2008.
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Measurement of pull-off force on imprinted nanopatterns in an inert liquid. NANOTECHNOLOGY 2010; 21:295306. [PMID: 20601765 DOI: 10.1088/0957-4484/21/29/295306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We report on the measurement of the pull-off force on nanoscale patterns that are formed by thermal nanoimprint lithography (t-NIL). Various patterns with feature sizes in the range of 50-900 nm were fabricated on silicon substrates using a rigiflex polymeric mold of ultraviolet curable polyurethane acrylate (PUA, Young's modulus approximately 1 GPa) or perfluoropolyether (PFPE, Young's modulus approximately 10.5 MPa) and a resist layer of polystyrene (PS) of three different molecular weights (M(w) = 18,100, 211,600 and 2043,000). The pull-off force was measured in non-polar, non-reactive perfluorodecalin (PFD) solvent between a sharp atomic force microscopy (AFM) tip and an imprinted pattern. Our experimental data demonstrated that the measured pull-off forces were in good agreement with a simple adhesion model based on Lifshitz theory. Also, the force on the pressed region (valley) is higher than that on the cavity region (hill), with the ratio (hill/valley) decreasing with the decrease of pattern size and the increase of molecular weight. The confinement effects were more pronounced for smaller patterns (<300 nm) and higher molecular weights (M(w) = 211,600 and 2043,000) presumably due to sluggish movement of polymer chains into nano-cavities. Finally, the experimental observations were compared with molecular dynamic simulations based on a simplified amorphous polyethylene model.
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Abstracts from the 6th International Conference on the Engineering of Sport, 10–14 July 2006, Olympic Hall, Munich, Germany. SPORTS ENGINEERING 2006. [DOI: 10.1007/bf02866061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Abstract
BACKGROUND Quantitative real-time polymerase chain reaction (Q-Rt-PCR) is a new tool in the detection and quantification of the BCR/abl fusion transcripts in chronic myelogenous leukemia (CML). This study investigates its specificity, sensitivity and potential clinical usefulness. PATIENTS AND METHODS Parallel analysis of Q-Rt-PCR and the conventional reverse transcription-mediated PCR (RT-PCR) were performed on 567 samples from 481 patients. Treatment response was monitored by Q-Rt-PCR at 6 and 12 months of 61 patients on STI-571 and 103 patients on interferon. RESULTS The concordance rate between Q-Rt-PCR and RT-PCR was 96.3% (546/567), with 341 positives and 205 negatives. The positive equivalents ranged from 2 x 10(-6) to 1.2 microg of K562 cell RNA. Karyotyping in 372 samples revealed excellent correlation with Q-Rt-PCR measurements (P < 0.001). Setting residual BCR/abl < 0.01 as an early goal of molecular response, we observed that STI-571 induced a better response than interferon: 49% (20 of 41 patients) versus 35% (15 of 62 patients) at 6 months (P = 0.025) and 52% (32 of 61 patients) versus 34% (35 of 103 patients) at 12 months (P = 0.01), respectively. CONCLUSIONS Q-Rt-PCR provides reliable measurements of BCR/abl fusion transcripts. It is potentially useful in assessing molecular residual disease after therapy.
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Abstract
This paper aims to remind paediatric clinicians to suspect and confirm 'PFAPA' syndrome (Periodic Fever, Aphthous stomatitis, Pharyngitis and cervical Adenitis syndrome). We report two cases of PFAPA syndrome: a 3-year-old healthy boy with atopic rhinitis and a boy aged 8 years 5 months who simultaneously had lymphocytic vasculitis syndrome treated with immunosuppressive drugs. Both met Marshall's criteria. The literature regarding PFAPA syndrome was complied using a Medline search for articles published between 1963 and 1998 and we then reviewed the reference lists of the articles. The Medline search revealed 28 cases with available clinical manifestations, management and prognosis. Our study describes two additional cases. We divided the cases into typical (28 cases) and atypical (two cases) PFAPA syndrome. In typical PFAPA, the age of onset was less than 5 years in most cases and the patients presented 4.9 +/- 1.4 days of fever (100%), pharyngitis (89.3%), cervical adenitis (72.1%), stomatitis (71.4%), malaise (64.3%), headache (60.7%), abdominal pain (53.6%) and nausea/vomiting (17.9%). Afebrile intervals were 3.2 +/- 2.4 months and increased with age. The time from initial onset to final episode was 3 years 7 months +/- 3 years 6 months. The total number of episodes was 8.3 +/- 2.5 (range 6-14). Effective treatment included steroids, tonsillectomy/adenoidectomy and cimetidine. The general outcome was good. In atypical PFAPF, the clinical manifestations were similar to those of typical PFAPA except that the age of onset was more than 5 years, and life-threatening intestinal perforation happened once in a patient with underlying Fanconi's anaemia. It was concluded that typical PFAPA syndrome is benign and can be diagnosed by detailed history-taking and from physical findings during repeated febrile episodes with tests to rule out other periodic fever syndromes. A review of the literatures since the first report in 1987 has shown that typical PFAPA syndrome is not associated with significant long-term sequelae and has a good response to steroids. One patient with atypical PFAPA, who received low-dose steroids for over 1 year, developed intestinal perforation after an increment of the 7-day steroid dose. If an underlying problem requires long-term immunosuppressive medication, it is wiser to choose cimetidine rather than increasing the steroid dosage to resolve atypical PFAPA.
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Spectral analysis by analogue time correlation of light scattered from macromolecule solutions. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3735/5/11/019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
To estimate the reaction of two primary redox-related species of nitric oxide (i.e. NO+ vs NO*) from a variety of NO donors, we employed the differential interactions of these NO forms with oxyhemoglobin (oxyHb) as a chemical assay. NO+ formation was estimated by the S-nitrosation reaction with oxyHb, and NO* formation via its reaction with the oxygen-heme complex of oxyHb. Under the conditions employed, all NO donors caused concentration-dependent formation of methemoglobin, indicative of NO* liberation. However, the extent of S-nitrosation was substantially different among the NO donors studied. A representative S-nitrosothiol, S-nitroso-N-acetyl-penicillamine, caused significantly more S-nitrosation than nitroglycerin, isobutyl nitrite, sodium nitroprusside, and 3-morpholino-sydnonimine (ANOVA, P < 0.05). These results indicated that NO donors can differ in their interactions with oxyHb, and possibly with other target proteins, in part because they liberate or transfer different ratios of NO redox forms. This difference may contribute, in part, to the diversity of pharmacological effects elicited by NO donors.
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Intraarticular triamcinolone hexacetonide injection in children with chronic arthritis: a survey of clinical practice. ACTA PAEDIATRICA TAIWANICA = TAIWAN ER KE YI XUE HUI ZA ZHI 1999; 40:182-5. [PMID: 10910611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
To assess the efficacy of the intraarticular steroid(IAS) injection in the management of arthritis and the possible related complications in children with chronic arthritis. We evaluated 11 children of chronic arthritis (4 girls and 7 boys), age of onset ranged from 2-13.6 years, who had persistent arthritis treated with IAS from November 1994 to June 1997. The results of injections showed that the beneficial effect was noted within one day to 2 weeks without significant adverse reactions, remission exceeding 6 months was seen in 10 of 11 patients (in 14 of 18 joints). According to subgroups of chronic arthritis, the remission rate of IAS injection in children with pauciarticular arthritis reached 100%. A significant fall in C-reactive protein (CRP) between pre- and post-IAS injection (p = 0.03), but there were no differences in hemoglobin (Hb), white blood cells (WBCs), thrombocytes (Plts), erythrocyte sedimentation rate (ESR) and osteocalcin level. No injection-related complications were found. In conclusion, the IAS injection was an effective and safe treatment in children with chronic arthritis with no obvious complications especially in pauciarticular arthritis.
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Pharmacokinetic and pharmacodynamic changes of furosemide after intravenous and oral administration to rats with alloxan-induced diabetes mellitus. Biopharm Drug Dispos 1998; 19:357-64. [PMID: 9737816 DOI: 10.1002/(sici)1099-081x(199809)19:6<357::aid-bdd114>3.0.co;2-g] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Because some physiological changes occurring in diabetes mellitus patients could alter the pharmacokinetics and pharmacodynamics of the drugs to treat the disease, the pharmacokinetics and pharmacodynamics of furosemide were investigated after intravenous (i.v.) and oral administration of the drug (6 mg per whole body weight) to control rats and alloxan-induced diabetes mellitus rats (AIDRs). After i.v. administration, the total body clearance (5.47 versus 7.05 mL min(-1) kg(-1)) was significantly slower in AIDRs and this was due to significantly slower renal clearance (2.35 versus 4.33 mL min(-1) kg(-1)) because the nonrenal clearance was comparable between two groups of rats. The 8 h urinary excretion of furosemide after i.v. administration decreased significantly (2280 versus 3760 microg) in AIDRs due to impaired kidney function; the glomerular filtration rate measured by creatinine clearance was significantly slower (2.86 versus 4.33 mL min(-1) kg(-1)) and both the plasma urea nitrogen (43.5 versus 17.3 mg dL(-1)) and kidney weight (0.953 versus 0.749% of body weight) increased significantly in AIDRs. This resulted in a significant decrease in the 8 h urine output per g kidney (17.8 versus 43.6 mL) in AIDRs. However, the 8 h diuretic efficiency was not significantly different between two groups of rats. After oral administration, the area under the plasma concentration-time curve from time 0 to 8 h decreased significantly in AIDRs (1200 versus 1910 microg x min mL(-1)) due to considerably decreased absorption of furosemide from gastrointestinal tract of AIDRs. After oral administration, the 8 h urine output per g kidney (18.6 versus 36.4 mL) also decreased significantly in the AIDRs due to significantly decreased 8 h urinary excretion of furosemide (405 versus 2210 microg), however, the 8 h diuretic efficiency increased significantly (127 versus 35.2 mL mg(-1)) in AIDRs.
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Abstract
The pharmacokinetics and pharmacodynamics of furosemide were compared after an oral administration or a direct administration of Lasix into the duodenum in humans (40 mg). Furosemide was absorbed quickly after a direct administration of Lasix into the duodenum; the peak plasma concentration of furosemide was reached within 1 h in both routes of administration, and the peak concentration was higher in all four subjects after a direct administration into the duodenum than after an oral administration. Furosemide was absorbed considerably after a direct administration of Lasix into the duodenum; the values of the area under the plasma concentration-time curves of furosemide from time zero to 4 h (AUC0-4 h, 93.6 versus 122 micrograms min mL-1, p < 0.123) and the cumulative amounts of the dose excreted in 8 h (10,600 versus 15,000 micrograms, p < 0.0185) and 24 h (11,300 versus 15,400 micrograms, p < 0.0192) urine as unchanged furosemide were significantly higher after a direct administration into the duodenum than after an oral administration. However, the amounts excreted in urine as glucuronide conjugates, a metabolite of furosemide, tended to increase after an oral administration (4030 versus 1670 micrograms as expressed in terms of furosemide, p < 0.0858) when compared to a direct administration into the duodenum, possibly due to the increased gastric first-pass metabolism of furosemide. The 8 h urine output and 8 h urinary excretion of sodium did not increase significantly after a direct administration of Lasix into the duodenum, despite the significantly greater amount of the drug delivered to the active site after a direct administration into the duodenum. This could be explained by the fact that the urinary excretion rates of furosemide after a direct administration into the stomach were closer to the values of maximally efficient urinary excretion rate of furosemide during the 8 h experimental period than after a direct administration into the duodenum.
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Abstract
The authors analyzed bone mineral density (BMD) in 283 postmenopausal and senile women using dual energy x-ray absorptiometry from March 1990 to April 1992. Bone mineral density of the vertebral body in the osteoporotic fracture group was compared with that in the osteoporotic group to investigate the correlation among BMD, age distribution, and fracture type, and to estimate fracture threshold in the osteoporotic fracture group. BMD decreased rapidly (10%) from 50 and 60 years of age and decreased slowly after 60 years of age; osteoporotic spine fractures were found in 98 cases (35%); there was significant difference in BMD between the osteoporotic group and osteoporotic fracture group; there was no spine fracture when BMD was above 1.00 g/cm2; fracture threshold was 0.85 g/cm2 at the 90th percentile; BMD in multiple spine fracture and old fracture groups was lower than in the single and fresh fracture groups and this was statistically significant. We have concluded that when BMD decreases to less than 0.85 g/cm2, the risk of osteoporotic vertebral fractures escalates rapidly. Postmenopausal and senile women with BMD less than this fracture threshold should receive prophylaxis for osteoporotic fracture.
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Pharmacokinetics of four metabolites of DA-125, a new anthracycline antineoplastic agent after single and multiple intravenous administration to rats. J Clin Pharm Ther 1996; 21:201-13. [PMID: 8933293 DOI: 10.1111/j.1365-2710.1996.tb01140.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The tissue distribution, and biliary and urinary excretion of four metabolites (M1-M4) of a new anthracycline antineoplastic agent (DA-125) were compared after single and multiple (7 consecutive days) intravenous (i.v.) administration to rats. The mean pharmacokinetic parameters of M1, such as area under the plasma concentration-time curve (AUC: 56.4 micrograms/ml vs. 69.0 micrograms min/ml), terminal half-life (t1/2: 3.51 h vs. 3.01 h), total body clearance (Cl: 70.9 ml/min/kg vs. 58.0 ml/min/kg), renal clearance (ClR: 0.193 ml/min/kg vs. 0.336 ml/min/kg) and nonrenal clearance (ClNR: 70.7 ml/min/kg vs. 57.7 ml/min/kg); of M2, such as plasma AUC (39.4 micrograms min/ml vs. 41.9 micrograms min/ ml), t1/2 (6.15 h vs. 7.34 h) and ClR (10.5 ml/min/ kg vs. 13.8 ml/min/kg); and of M4, such as plasma AUC (4.82 micrograms min/ml vs. 6.54 micrograms min/ml) and t1/2 (3.33 h vs 4.02 h), were comparable between single and multiple administrations of DA-125. M3 was detected in plasma for up to 1-5 min, and M3 and M4 were below the detection limit in 24-h urine after both single and multiple administrations of DA-125. M2 was the main metabolite of DA-125 excreted (among M1-M4) in 24-h urine after both single and multiple administrations of DA-125; approximately 12.3% and 20.1% (P < 0.01) of i.v. dosage (expressed in terms of DA-125) was excreted as M2 after single and multiple administrations of DA-125, respectively. Corresponding values for M1 were 0.326% and 0.694% (P < 0.05). The mean levels of M1 (229 micrograms vs. 175 micrograms) and M2 (1330 micrograms vs. 1120 micrograms) excreted in 24-h bile after single and multiple administrations of DA-125 were not significantly different; the percentages of i.v. dosage excreted in 24-h bile as M1 (expressed in terms of DA-125) were 4.83% and 3.58% after single and multiple administrations, respectively. The corresponding values for M2 were 27.8% and 22.5%. M3 and M4 were below the detection limit in 24-h bile after both single and multiple administrations of DA-125. Mean AUAts (area under the amount-time curves from time zero to last measurement time t) (or AUCts-area under the plasma concentration-time curves from time zero until the last measurement time t) of M1-M4 in each tissue after single and multiple administrations of DA-125 were also comparable except in the bone marrow and thymus. The data suggest that 7 consecutive days of i.v. administration of DA-125 (4 mg/kg) to rats does not lead to considerable accumulation of M1-M4 in the tissues, except in the bone marrow and thymus.
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Comparison of pharmacokinetics of M1, M2, M3, and M4 after intravenous administration of DA-125 or ME2303 to mice and rats. New adriamycin analogues containing fluorine. Biopharm Drug Dispos 1996; 17:373-420. [PMID: 8830976 DOI: 10.1002/(sici)1099-081x(199607)17:5<373::aid-bdd373>3.0.co;2-u] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The pharmacokinetics of M1, M2, M3 and/or M4 were compared after intravenous (i.v.) administration of DA-125 and/or ME2303 to mice (25 mg kg(-1)) and rats (5, 10, 20, 30, and 40 mg kg(-1)). The mean plasma concentrations of M1 were detected up to 8 h after i.v. administration of both DA-125 and ME2303 to mice, and were significantly higher for DA-125 than ME2303; this resulted in a considerably greater AUC (303 against 148 micrograms min mL(-1)) and a considerably slower CL of M1 (69.3 against 136 mL min-1 kg(-1)) after i.v. administration of DA-125. The MRT (371 against 189 min) and CLNR of M1 (68.7 against 136 mL min-1 kg(-1)) were considerably greater and slower, respectively, after i.v. administration of DA-125. The mean plasma concentrations of M2 were detected up to 8 and 4 h after i.v. administration of DA-125 and ME2303, respectively, to mice and were significantly higher for DA-125 than ME2303, resulting in a considerably greater AUC of M2 (148 against 27.1 micrograms min mL(-1)) after i.v. administration of DA-125. The mean plasma concentrations of M3, being the lowest among M1-M4, were detected only up to 15 min after i.v. administration of both DA-125 and ME2303 to mice, and were comparable after i.v. administration of DA-125 and ME2303 to mice. The mean plasma concentrations of M4 were detected up to 8 h after i.v. administration of both DA-125 and ME2303 to mice, and were higher after i.v. administration of DA-125 than ME2303, resulting in a considerably greater AUC of M4 (197 against 61.9 micrograms min mL(-1)) after i.v. administration of DA-125. Similar results on M1 and M2 were also obtained from rats: the mean plasma concentrations of both M1 and M2 were significantly higher after i.v. administration of DA-125, 10 mg kg(-1), than after ME2303. The plasma concentrations of M1, M2, and M4, and hence their AUCs, were significantly higher after i.v. administration of DA-125, 5, 10, 20, 30, and 40 mg kg(-1), to rats than after ME2303: the mean plasma concentrations of M2, approximately 0.1-0.4 micrograms mL(-1), were maintained from 30 min to 8-10 h after i.v. administration of DA-125, 20, 30, and 40 mg kg(-1), to rats; the plasma concentrations of M3 were the lowest among M1-M4 at all DA-125 doses; and those of M1 and M4 were maintained for a long period of time. However, after i.v. administration of M2, 5 mg kg(-1), to rats, the mean plasma concentrations of M2 were detected up to 60 min with a mean terminal half-life of only 38.8 min, and the concentrations of M3 were negligible. After i.v. administration of M3, 5 mg kg(-1), to rats, the mean plasma concentrations of M3 were detected up to 15 min; the plasma concentrations of M4, reaching their peak at 5 min, decayed more slowly and were higher than those of M3. The AUC of M4 after i.v. administration of M3, 5 mg kg(-1), was comparable to that after i.v. administration of M4, 5 mg kg(-1), to rats, suggesting that M4 is formed fast and almost completely from M3. M1 was not detected in plasma after i.v. administration of either M2 or M3 to rats. After i.v. administration of M4, 5 mg kg(-1), to rats, the mean plasma concentrations of M4 decayed fast with a mean terminal half-life of 43.9 min and neither M2 nor M3 were detected in plasma. The following disposition mechanisms for M1, M2, M3, and M4 after i.v. administration of DA-125 to rats could be obtained from the above data; (i) the maintenance of plasma concentrations of M2 for a longer period of time after i.v. administration of DA-125 than those after i.v. administration of M2 could be due to the continuous formation of M2 from M1; (ii) the lowest plasma concentrations of M3 among M1-M4 after i.v. administration of DA-125 could be due to the fast and almost complete information of M4 from M3 as soon as M3 is formed from M1, and not due to the fast renal excretion of unchanged M3; (iii) M4 was exclusively and continuously formed from M3 and the formation of M4 from M2 was negligible; and (i.v.) reversible me
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Abstract
BACKGROUND & AIMS Bowel ischemia and perforation is an infrequent but ominous event in patients with malignant lymphoma. The underlying pathogenesis of this association remains to be clarified in most cases. Seven unusual cases of angiocentric T-cell lymphoma of the intestine presenting with bowel ischemia or perforation are reported. Their clinicopathologic features were analyzed. METHODS Clinical records and histopathology were reviewed. Immunophenotypic studies and EBER1 in situ hybridization for Epstein-Barr virus were performed. RESULTS All patients (3 men and 4 women; mean age, 42 years) presented with acute abdominal pain, bloody stool, or bowel perforation. The intestinal lesions were ulcerated and transmurally necrotic or gangrenous. The angiodestruction of the tumor cells appeared to be responsible for the presenting bowel ischemia. The neoplastic cells expressed a pan-T-cell antigen CD45RO; 4 of them contained Epstein-Barr virus transcripts EBER1. The prognosis was grave; 6 patients died within 3 months of onset. CONCLUSIONS Intestinal angiocentric T-cell lymphoma represents a distinct etiology of bowel ischemia. The condition should be taken into consideration, particularly in young adults with ischemic bowel disease.
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Factors influencing the protein binding of YH-439 using an equilibrium dialysis technique. A new hepatoprotective agent. Biopharm Drug Dispos 1995; 16:775-89. [PMID: 8580401 DOI: 10.1002/bdd.2510160907] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Various factors influencing the plasma protein binding of YH-439 to 4% human serum albumin (HSA) were evaluated using the equilibrium dialysis method at the initial YH-439 concentration of 2 micrograms mL-1. It took approximately 12 h of incubation to reach an equilibrium between 4% HSA and isotonic phosphate buffer of pH 7.4 containing 3% of dextran ('the buffer') using a Spectra/Por 2 membrane (molecular weight cut-off, 12,000-14,000) in a water bath shaker kept at 37 degrees C and at a rate of 50 oscillations min-1. YH-439 was fairly stable both in 4% HSA and in the 'buffer' for up to 24 h incubation. The binding of YH-439 to 4% HSA was constant (97.4 +/- 0.55%) at YH-439 concentrations ranging from 0.5 to 10 micrograms mL-1. However, the extent of binding was dependent on HSA concentrations: the values were 90.7, 94.7, 96.7, 97.0, 97.0, 97.1, and 97.5% at HSA concentrations of 0.5, 1, 2, 3, 4, 5, and 6%, respectively. The plasma protein binding decreased with increasing incubation temperature: the binding values were 98.2, 97.6, 97.2, and 96.8% when incubated at 10, 21, 26, and 37 degrees C, respectively. The binding of YH-439 was also influenced by the chloride concentration in the buffer: the binding values were 94.5, 97.0, and 96.8% for the chloride concentrations of 0, 0.249, and 0.546%, respectively. The binding of YH-439 was also dependent on the buffer pH: the percentages of free fraction were 6.0, 4.1, 3.8, 2.8, 2.7 and 2.8% for the buffer pHs of 5.0, 6.0, 6.5, 7.0, 7.4, and 8.0, respectively. The free fraction of YH-439 was slightly increased by the addition of heparin (up to 40 U mL-1), sodium azide (NaN3, up to 0.5%), and its metabolites. The protein binding of YH-439 was influenced neither by AAG, acetylsalicylic acid, or sulphisoxazole, nor by the addition of citrate or EDTA. The free fractions of YH-439 in rabbit (4.2%) and dog (4.7%) plasma seemed to be higher than in rats (2.9%) and humans (3.1%).
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Pharmacokinetics and antitumour activity of a new anthracycline, DA-125, after intravenous administration to subcutaneously implanted Lewis-lung-carcinoma-bearing mice. Biopharm Drug Dispos 1995; 16:489-505. [PMID: 7579031 DOI: 10.1002/bdd.2510160607] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The pharmacokinetics and tissue distribution of M1-M4 were compared after intravenous (i.v.) administration of DA-125, 25 mg kg-1, to BDF1 mice (n = 5 at each sampling time) and subcutaneously implanted Lewis-lung-carcinoma-bearing BDF1 mice (n = 10 at each sampling time. The mean plasma concentrations of M1-M4 were not significantly different between the two groups of mice, and hence similar pharmacokinetic parameters for M1-M4 were obtained. The amount of M1 in the lung was significantly greater in the tumour-bearing mice than in the control mice, resulting in a greater AUAt in the tumour-bearing mice (18,600 against 8940 micrograms min g-1), and vice versa in the liver (962 against 3840 micrograms min g-1). However, the corresponding values for other tissues were comparable between the control and tumour-bearing mice. The amount of M1 was greatest in the lung for up to 2 h in the tumour-bearing mice. M2 was the predominant metabolite among M1-M4 excreted in 24 h urine by both groups of mice; 8.36 and 10.7% of the i.v. dose were excreted in 24 h urine as M2--expressed in terms of DA-125--by the control and tumour-bearing mice, respectively. The amount of M1 in the tumour mass reached a mean Cmax of 3.75 micrograms g-1 immediately after i.v. administration of DA-125 to the tumour-bearing mice, then declined very slowly to an amount that remained almost constant for up to 24 h. This suggested that M1 has high affinity for the subcutaneously implanted Lewis lung carcinoma. The antitumour activity, such as the increase in life span (ILS) and tumour growth inhibition (TGI) of DA-125, 6-48 mg kg-1, and adriamycin (ADM), 3-18 mg kg-1, were also compared in subcutaneously implanted Lewis-lung-carcinoma-bearing BDF1 mice after four weekly i.v. administration of the drugs on days 1,8,15, and 22 following tumour implantation. More than three out of six mice survived as tumour-free for longer than 70 d at a DA-125 dose range of 6-24 mg kg-1, but there were no tumour-free mice at any dose of ADM. Assuming ILS values higher than 30% to be effective, DA-125 doses ranging from 6 to 24 mg kg-1 were effective in increasing the life span, which ADM does only within the dose range of 6-12 mg kg-1.
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The effect of water deprivation on the pharmacokinetics of methotrexate in rats. Biopharm Drug Dispos 1995; 16:245-50. [PMID: 7787136 DOI: 10.1002/bdd.2510160309] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Bone marrow findings before and after treatment with recombinant human erythropoietin in chronic hemodialyzed patients. Clin Nephrol 1995; 43:189-95. [PMID: 7774077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The stimulating effect of rHuEPO on erythropoiesis has been shown in several studies, using bone marrow cell culture or animal models. To investigate the effect of rHuEPO on bone marrow findings in vivo, we studied the bone marrow cellularity, the myeloid: erythroid (M:E) ratio, an estimate of the number of megakaryocytes, any cytomorphologic or maturation abnormalities, and an estimate of the storage iron before and after 3 months of treatment with rHuEPO in 10 chronic hemodialyzed patients. Nine patients showed a slight or moderate decrease of erythropoiesis in bone marrow in comparison to normal bone marrow before rHuEPO treatment. The bone marrow cellularity was a mean of 28.5% and decreased in 8 out of 10 patients compared to normal values. However, megakaryopoiesis and granulopoiesis were normal. Three months of treatment with rHuEPO had increased erythropoiesis in all 10 patients, including one patient whose bone marrow proved to be normal erythropoiesis on baseline examination. The M:E ratio was significantly decreased from 4.0 +/- 1.2:1 to 2.4 +/- 1.1:1 (p < 0.005). The bone marrow cellularity was also increased in 9 patients, except in 1 patient whose specimen was inadequate for diagnosis, after 3 months of treatment with rHuEPO. On baseline examination of bone marrow, iron staining was undetectable in one, low in one, normal in 2 and high in 5 sections. According to grading, iron staining had decreased from 3.1 +/- 1.7 to 2.1 +/- 0.9 (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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Abstract
We retrospectively studied 156 patients with non-Hodgkin's; ymphoma (NHL) in order to evaluate the incidence of bone marrow (BM) involvement at the time of diagnosis. The incidence of marrow involvement in NHL was 35% (55 patients). The most common histologic type of lymphoma was diffuse large cell lymphoma with 30% of the cases having bone marrow involvement. The highest incidence of marrow involvement was seen in immunoblastic lymphoma & the lowest incidence in diffuse mixed cell lymphoma. Bone marrow lymphoma was present in 50% of low-, 34% of intermediate-, and 55% of high-grade lymphomas. B-cell vs T-cell lymphoma in cases of marrow involvement was 56% to 42%. The most frequent pattern of marrow involvement was interstitial & diffuse (56% & 31%). The paratrabecular pattern was rare (4%). Most lymphomas (42%) extensively involved marrow space greater than 76% of the total marrow space. Discordant histology between lymph node and BM was seen in 10 cases (18%). Biopsy was the best method compared to smear & clot section (sensitivity 82% vs 72% vs 69%). In conclusion, our study revealed that the most common histologic type of marrow lymphoma was diffuse large cell type with frequent interstitial and diffuse pattern and extensive involvement of the marrow space. No predilection for a trabecular pattern was found. This result was in contrast to that in the Western literature.
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Pelvic actinomycosis with colo-ileo-vesical fistula formation: report of a case. J Formos Med Assoc 1992; 91:342-5. [PMID: 1354699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023] Open
Abstract
Pelvic actinomycosis with multiple fistular formation is rarely reported in the literature. We herein present a case of pelvic actinomycosis with sigmoid colo-ileovesical fistulae in a 36-year-old intrauterine device (IUD) user. She was admitted to the hospital because of general malaise, weight loss and bilateral palpable adnexal masses. Sonography showed bilateral adnexal masses which contained many echolucent spots. A barium enema examination revealed sigmoid colo-ileo-vesical fistulae. A computed tomographic scan showed bilateral cystic adnexal masses, bilateral hydronephrosis and hydroureter. Preoperatively, pelvic malignancy was suspected. An exploratory laparotomy was performed. Bilateral tubo-ovarian abscesses with extensive adhesions were found. Pathologic examination of the operative specimen revealed pelvic actinomycosis. The patient was treated with penicillin for 14 weeks and had a stable clinical course.
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Fibre-optic laser instrument for measuring ciliary activity of oviducts in vitro. Med Biol Eng Comput 1988; 26:655-8. [PMID: 3256760 DOI: 10.1007/bf02447506] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Abstract
An in vitro study was designed using the laser light-scattering technique to obtain further information on the dose-effect relationship of methylmercury on sperm motility. The technique provided a quantitative evaluation of sperm swimming speed. Semen samples were collected from normal male Macaca fascicularis monkeys by anal electroejaculation. Methylmercury was added to aliquots of sperm suspensions in BWW medium in doses of 10, 5, 2, and 1 ppm. After 3 hours, the relative speed was 35%, 59%, 69%, and 92% of the corresponding controls at doses of 10, 5, 2, and 1 ppm, respectively. The percentage of motile spermatozoa decreased significantly at 10 ppm. By microscopic observation abnormal motility was detected at 5 and 10 ppm, especially after 20 to 40 minutes. Head movement increased from side to side, and many spermatozoa developed coiled tails. The technique proved useful for defining the dose-effect relationship of methylmercury and sperm swimming speed.
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Selection of human spermatozoa according to their relative motility and their interaction with zona-free hamster eggs. Fertil Steril 1983; 40:655-60. [PMID: 6628710 DOI: 10.1016/s0015-0282(16)47426-1] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Human spermatozoa were separated according to their motility by centrifuging semen on discontinuous Percoll gradients. Fractions of the gradients were examined for sperm motility, velocity, viability, morphology, bacteria, and sperm function using the hamster ova sperm penetration assay. The percentage of motile sperm increased from 40% to 60% motile sperm in 60% Percoll to 90% to 100% Percoll. Sperm velocity increased proportionately. Staining showed that greater than 90% of sperm in the 100% Percoll were alive and had normal morphology, and that only sperm cells were found in Percoll concentrations greater than 80%. Sperm isolated in the 80% to 100% Percoll fractions penetrated hamster ova much more frequently than sperm found in the 60% to 70% fractions or than sperm that had not been separated on a Percoll gradient.
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Laser light-scattering study of the effect of washing on sperm motility. Fertil Steril 1982; 38:62-7. [PMID: 7095169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The effect of washing on human sperm motility was measured by means of dynamic laser light-scattering spectroscopy. Semen samples from 24 fertile donors were diluted with Biggers, Whitten and Whittingham (BWW) medium and subsequently centrifuged at one of the following forces: 235 x g, 325 x g, 400 x g, 470 x g, 500 x g, 600 x g, and 800 x g. The duration of centrifugation was 8 minutes for the first wash, 6 minutes for the second wash, and 3 minutes for the third wash. Sperm motility was evaluated in terms of the root mean square swimming speed of the spermatozoa and the mean migration rate of washed spermatozoa in estrous bovine cervical mucus (BCM). It was found that sperm motility and viability were improved when semen samples were washed at 235 x g, even after three washes. However, washing at forces of 600 x g or more reduced sperm motility and also their ability to penetrate cervical mucus in vitro. Repeated washing at forces between 300 x g and 500 x g had little deleterious effect on sperm motility.
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Sperm penetration into cervical mucus in vitro. III. Effect of freezing on estrous bovine cervical mucus. Fertil Steril 1981; 36:209-13. [PMID: 6894904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The influence of the storages period on estrous bovine cervical mucus after it was stored in the freezing compartment of the laboratory refrigerator was evaluated by an in vitro sperm penetration test with human spermatozoa, laser light-scattering, and a spinnbarkeit test. Data obtained from the sperm penetration test were analyzed by a mathematical model that correlates the sperm motility with the sperm transport rate and the penetrability of the mucus. The tests showed that estrous bovine cervical mucus can be stored for up to 4 weeks at -12 degrees C without a change in its physical properties. The results of this study strengthen the suggestion that bovine mucus could be employed as a substitute for human cervical mucus.
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Sperm penetration into cervical mucus in vitro. I. Comparative studies. Fertil Steril 1980; 33:636-43. [PMID: 7380050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Comparative studies have been carried out on the behavior of human and bovine spermatozoa toward homologous cervical mucus in vitro. In both cases the degree of sperm penetration and the pattern of sperm motility were influenced in a characteristic fashion by prior manipulation of the mucus: the most rapid and extensive penetration, and pronounced unidirectional motion, were seen in mucus that had been aligned linearly. By contrast, spermatozoa from rabbits, guinea pigs, rats, and mice were largely prevented from entering either midcycle human or estrous bovine cervical mucus, regardless of its physical arrangement. The observations on sperm motility patterns and the degree of penetration are discussed in relation to a model of the molecular arrangement of cervical mucus, derived in our laboratory from laser light-scattering spectroscopy.
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Sperm penetration into cervical mucus in vitro. II. Human spermatozoa in bovine mucus. Fertil Steril 1980; 33:644-8. [PMID: 7189721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Human spermatozoa pentrate estrous bovine cervical mucus readily in vitro and maintain good motility and viability for a number of hours. They show pronounced unidirectional motion in mucus that has been aligned linearly. Data from tube preparations indicate that human spermatozoa from a given ejaculate travel more rapidly in estrous bovine mucus than in human midcyle mucus. They are prevented from penetrating luteal phase bovine mucus. The results are discussed in relation to a model of the molecular structure of cervical mucus, derived from laser light-scattering spectroscopy. In addition, it is suggested that bovine cervical mucus could be developed as a possible substitute for human cervical mucus in cases of infertility due to deficient endogenous mucus.
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Abstract
A mathematical description of ovum transport based on Langevin's diffusion equation is presented. The proposed model is deduced from qualitative features of this phenomenon, not induced from numerical fitting of experimental data. We demonstrate that egg transport in the ampulla of the rabbit oviduct can be represented as a one-dimensional random walk in a field of external force. The application of the model to describe isthmic ovum and sperm transport on the basis of simple random walk process is also discussed. The present formulation identifies and characterizes the forces involved in the motions of the ovum and predicts specific alternatives for physiological regulation of egg transport in the oviduct.
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Laser light-scattering study of the effect of progesterone on sperm motility. Fertil Steril 1979; 32:320-3. [PMID: 488413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
It is known that progestins can induce in the secretory cells of the cervix the excretion of a mucus that is highly viscuos, scanty, and impenetrable to spermatozoa. Mucus of this type is similar to that excreted during the luteal phase of the normal human menstrual cycle and the cow estrous cycle. It is a natural sequence to ask the question, do progestins also have a direct effect on sperm motility? With dynamic laser light-scattering we measured the motility of freshly washed human spermatozoa and of spermatozoa in the presence of a progesterone, both in terms of their swimming speed distribution as expressed in the spectrum of scattered light. The swimming speed was significantly reduced when the concentration of progesterone was three orders of magnitude greater than that of the physiologic level. This finding confirms the finding in earlier biochemical studies that progesterone has a distinct spermiostatic effect. We suggest this answer to the above question: progestin-releasing contraceptive devices may act on spermatozoa directly as well as in the secretory cells of the cervix.
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Cervical mucus deficiency. Fertil Steril 1978; 29:707. [PMID: 658486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Dynamic light-scattering studies of DNA. I. The coupling of internal modes with anisotropic translational diffusion in congested solutions. Biopolymers 1977; 16:583-99. [PMID: 843605 DOI: 10.1002/bip.1977.360160309] [Citation(s) in RCA: 40] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Abstract
A uniquely precise and simple method to study ciliary activity by laser light-scattering spectroscopy has been developed and validated. A concurrent study of the effect of Ca2+ on ciliary activity in vitro by laser scattering spectroscopy and high speed cinematography has demonstrated that this new method is simpler and as accurate and reproducible as the high speed film technique.
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