Direct Measurement of Human Cervical Tissue Permeability

2012 ◽  
Author(s):  
Michael Fernandez ◽  
Joy Vink ◽  
Ronald Wapner ◽  
Kyoko Yoshida ◽  
Kristin M. Myers
Keyword(s):  
Direct Measurement ◽  
Previous History ◽  
Cervical Tissue ◽  
Confined Compression ◽  
Tissue Samples ◽  
Developmental Problems ◽  
History Of ◽  
Research Goal ◽  
Softening Process

The mechanical integrity of the uterine cervix is critical for the full-term success of a pregnancy. It must be strong to retain the fetus throughout gestation and then undergo a remodeling and softening process before labor to allow dilation and delivery. We hypothesize that the preterm birth (PTB) condition known as cervical insufficiency (CI) is related to a weak or soft cervix. Such PTBs are responsible for infant developmental problems and in severe cases, infant mortality. To understand the etiologies of CI, our overall research goal is to investigate the mechanical behavior of the cervix. As a foundation for future in-vivo tools to assess cervical softness, we aim to quantify cervical structure-material property relationships for nonpregnant (NP) and pregnant (PG) tissue from women with different obstetric backgrounds, including women with a previous history of CI. The goal of this study is to characterize cervical tissue as a poroelastic (biphasic) material. Here we present the results of two mechanical experiments on NP and PG hysterectomy cervical tissue samples: first, confined compression and second, direct measurement of permeability by a custom strain-adjustable permeation rig.

scholarly journals Digital dermatitis of the accessory digits of dairy cows

2010 ◽  
Vol 30 (3) ◽  
pp. 246-248
Author(s):  
Celso A. Rodrigues ◽  
Maria C.R. Luvizotto ◽  
Ana Liz G. Alves ◽  
Piero H.M. Teodoro ◽  
Elisa A. Gregório
Keyword(s):  
Dairy Cows ◽  
Previous History ◽  
Dairy Farms ◽  
Response To Therapy ◽  
Holstein Cattle ◽  
Electronic Microscopy ◽  
Digital Dermatitis ◽  
Tissue Samples ◽  
History Of ◽  
Long Acting

This report characterizes the digital dermatitis (DD) lesions in the accessory digits of dairy cows and presents data on the applied therapy. Fifteen Holstein cattle with DD affecting the accessory digits of the hindlimbs from four dairy farms with previous history of DD were evaluated. Lesions were excised, the wounds were sutured, and a topical application of oxytetracycline powder covered by bandaging was associated with a single parenteral administration of long acting oxytetracycline IM (20mg/kg). Tissue samples were obtained for histopathology and transmission electronic microscopy (TEM). Lesions from all the animals were recuperated 15 days after surgical procedure. Overal, most DD lesions were papillomatous epidermal projections or wartlike verrucous lesions. Histopathologically, samples revealed hyperplasia of epidermis with hyperkeratosis, several mitoses in the stratum basale and elongated rete ridges in the superficial and middle dermis. TEM revealed long, thin spirochete-like bacteria. Morphologic features of lesions and its response to therapy were comparable to those described for DD.

scholarly journals Cardio-pathogenic variants in unexplained intrauterine fetal death: a retrospective pilot study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dana A. Muin ◽  
Martina Kollmann ◽  
Jasmin Blatterer ◽  
Gregor Hoermann ◽  
Peter W. Husslein ◽  
...  
Keyword(s):  
Fetal Death ◽  
Previous History ◽  
Intrauterine Fetal Death ◽  
Post Mortem ◽  
University Hospitals ◽  
Tissue Samples ◽  
Pathogenic Variants ◽  
Uncertain Significance ◽  
History Of ◽  
Genetics And Genomics

AbstractTo describe the prevalence and spectrum of cardio-pathogenic variants in singleton fetuses after unexplained intrauterine fetal death (IUFD). DNA from post-mortem fibroblastic tissue samples of 16 fetuses after unexplained IUFD was retrieved at two tertiary university hospitals for clinical exome sequencing with subsequent filtering of 122 cardio-specific genes to elucidate underlying cardio-pathogenic variants. In total, we included 12 (75%) male and four (25%) female fetuses who were stillborn at a median gestational age of 34+6 (23+2–40+5) weeks. In two (12.5%) fetuses no cardio-pathogenic variants were found. In 14 (87.5%) fetuses, overall 33 variants were detected in 22 cardio-specific genes, involving 14 (63.63%) genes associated with cardiomyopathy, six (27.27%) arrhythmogenic susceptibility genes and two (9.09%) arrhythmia and cardiomyopathy associated genes. Among the 33 variants, five (15.2%) were classified as likely benign according to the American College of Medical Genetics and Genomics; 28 (84.8%) variants were considered as variants of uncertain significance. Compared to a cohort of explained IUFDs, the cases with and without fetal variants in cardiac genes differed not significantly regarding maternal age, previous history of stillbirth, time of stillbirth or fetal sex. Unexplained stillbirth may be caused by cardio-genetic pathologies, yet a high number of variants of uncertain significance merit a more detailed post-mortem examination including family segregation analysis.

Direct Measurement of the Permeability of Human Cervical Tissue

2013 ◽  
Vol 135 (2) ◽  
Author(s):  
Michael Fernandez ◽  
Joy Vink ◽  
Kyoko Yoshida ◽  
Ronald Wapner ◽  
Kristin M. Myers
Keyword(s):  
Mechanical Behavior ◽  
Material Behavior ◽  
Patient Specific ◽  
Diagnostic Tools ◽  
Hydraulic Permeability ◽  
Cervical Tissue ◽  
Large Variability ◽  
Developmental Problems ◽  
External Forces

The mechanical integrity of the uterine cervix is critical for a pregnancy to successfully reach full term. It must be strong to retain the fetus throughout gestation and then undergo a remodeling and softening process before labor for delivery of the fetus. It is believed that cervical insufficiency (CI), a condition in pregnancy resulting in preterm birth (PTB), is related to a cervix with compromised mechanical strength which cannot resist deformation caused by external forces generated by the growing fetus. Such PTBs are responsible for infant developmental problems and in severe cases infant mortality. To understand the etiologies of CI, our overall research goal is to investigate the mechanical behavior of the cervix. Permeability is a mechanical property of hydrated collagenous tissues that dictates the time-dependent response of the tissue to mechanical loading. The goal of this study was to design a novel soft tissue permeability testing device and to present direct hydraulic permeability measurements of excised nonpregnant (NP) and pregnant (PG) human cervical tissue from women with different obstetric histories. Results of hydraulic permeability testing indicate repeatability for specimens from single patients, with an order of magnitude separating the NP and PG group means (2.1 ± 1.4×10-14 and 3.2 ± 4.8×10-13m4/N·s, respectively), and large variability within the NP and PG sample groups. Differences were found between samples with similar obstetric histories, supporting the view that medical history may not be a good predictor of permeability (and therefore mechanical behavior) and highlighting the need for patient-specific measurements of cervical mechanical properties. The permeability measurements from this study will be used in future work to model the constitutive material behavior of cervical tissue and to develop in vivo diagnostic tools to stage the progression of labor.

Permeability of the Organ of Corti

1973 ◽  
Vol 82 (2) ◽  
pp. 166-174 ◽  
Author(s):  
Allan J. Goldstein
Keyword(s):  
Hair Cell ◽  
Hair Cells ◽  
Membrane Structure ◽  
Previous History ◽  
Organ Of Corti ◽  
Large Molecules ◽  
History Of ◽  
Cellular Permeability ◽  
Stimulation Of

The technique of fluorochromasia has been used to study cellular permeability of the inner ear tissues. The hair cells of the organ of Corti show variations in permeability which are dependent on the previous history of in vivo exposure to physiologically normal levels of sound. Permeability was also sensitive to oxygen deprivation. Gross mechanical stimulation of the hair cells is sufficient to render the hair cell permeable to large molecules. The cilia of the hair cells seem to have a membrane structure independent of the hair cell itself.

Biomedical applications: Pitfalls in the practice

1994 ◽  
Vol 52 ◽  
pp. 378-379
Author(s):  
J. D. Shelburne ◽  
Peter Ingram ◽  
Victor L. Roggli ◽  
Ann LeFurgey
Keyword(s):  
Operating Room ◽  
Liquid Nitrogen ◽  
Lung Tissue ◽  
Biomedical Applications ◽  
Microprobe Analysis ◽  
Tissue Sample ◽  
Cellular Level ◽  
Tissue Samples ◽  
Asbestos Fibers

At present most medical microprobe analysis is conducted on insoluble particulates such as asbestos fibers in lung tissue. Cryotechniques are not necessary for this type of specimen. Insoluble particulates can be processed conventionally. Nevertheless, it is important to emphasize that conventional processing is unacceptable for specimens in which electrolyte distributions in tissues are sought. It is necessary to flash-freeze in order to preserve the integrity of electrolyte distributions at the subcellular and cellular level. Ideally, biopsies should be flash-frozen in the operating room rather than being frozen several minutes later in a histology laboratory. Electrolytes will move during such a long delay. While flammable cryogens such as propane obviously cannot be used in an operating room, liquid nitrogen-cooled slam-freezing devices or guns may be permitted, and are the best way to achieve an artifact-free, accurate tissue sample which truly reflects the in vivo state. Unfortunately, the importance of cryofixation is often not understood. Investigators bring tissue samples fixed in glutaraldehyde to a microprobe laboratory with a request for microprobe analysis for electrolytes.

405: Previous History of Bladder Cancer is an Independent Prognostic Factor for Upper Tract Transitional Cell Carcinoma

2007 ◽  
Vol 177 (4S) ◽  
pp. 135-135
Author(s):  
Eiji Kikuchi ◽  
Akira Miyajima ◽  
Ken Nakagawa ◽  
Mototsugu Oya ◽  
Takashi Ohigashi ◽  
...  
Keyword(s):  
Bladder Cancer ◽  
Prognostic Factor ◽  
Transitional Cell Carcinoma ◽  
Cell Carcinoma ◽  
Transitional Cell ◽  
Previous History ◽  
Independent Prognostic Factor ◽  
Upper Tract ◽  
History Of

Popliteal artery thrombosis secondary to a tibial osteochondroma

VASA ◽  
2011 ◽  
Vol 40 (3) ◽  
pp. 251-255 ◽  
Author(s):  
Gruber-Szydlo ◽  
Poreba ◽  
Belowska-Bien ◽  
Derkacz ◽  
Badowski ◽  
...  
Keyword(s):  
Case Report ◽  
Magnetic Resonance Angiography ◽  
Popliteal Artery ◽  
Doppler Ultrasonography ◽  
Histopathological Examination ◽  
Previous History ◽  
Plain Radiography ◽  
Artery Thrombosis ◽  
History Of ◽  
The Right

Popliteal artery thrombosis may present as a complication of an osteochondroma located in the vicinity of the knee joint. This is a case report of a 26-year-old man with symptoms of the right lower extremity ischaemia without a previous history of vascular disease or trauma. Plain radiography, magnetic resonance angiography and Doppler ultrasonography documented the presence of an osteochondrous structure of the proximal tibial metaphysis, which displaced and compressed the popliteal artery, causing its occlusion due to intraluminal thrombosis..The patient was operated and histopathological examination confirmed the diagnosis of osteochondroma.

Scintigraphic Detection of Experimental Myocardial Infarction with 99mTc-2,3-Dimercaptosuccinic Acid

1984 ◽  
Vol 23 (06) ◽  
pp. 317-319
Author(s):  
J. Novák ◽  
Y. Mazurová ◽  
J. Kubíček ◽  
J. Yižd’a ◽  
P. Kafka ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Coronary Artery ◽  
Intravenous Administration ◽  
Experimental Myocardial Infarction ◽  
Myocardial Infarctions ◽  
Clinical Use ◽  
Scintigraphic Imaging ◽  
Tissue Samples ◽  
Scintigraphic Finding

SummaryAcute myocardial infarctions were produced by ligature of the left frontal descending coronary artery in 9 dogs. The possibility of scintigraphic imaging with 99mTc-DMSA 4 hrs after intravenous administration was studied. The infarctions were 4, 24 and 48 hrs old. The in vivo scan was positive in only one dog with a 4-hr old infarction. The in vivo scans were confirmed by the analysis of the radioactivity in tissue samples. The accumulation of the radiopharmaceutical increased slightly in 48-hr old lesions; however, this increase was not sufficient for a positive scintigraphic finding. Thus, we do not recommend 99mTc-DMSA for clinical use in acute lesions.

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