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PubMed2001

Extending the Aberdeen Back Pain Scale to include the whole spine: a set of outcome measures for the neck, upper and lower back.

Many therapists treat the spine as a 'functional unit', but suitable condition-specific outcome measures for the whole spine are not available. One of the most rigorously tested measures for back pain related health status is the Aberdeen Back Pain Scale, but it is only suitable for the lower back. The Aberdeen Back Pain Scale was extended to create a set of interlocking outcome measures for the neck, upper and lower back. Questions in these extended outcome measures had to fulfil a series of psychometric criteria before being accepted into the final questionnaires. This involved response frequency, item-total correlation and principal component analysis. The final questionnaires were tested for reliability, criterion and construct validity, responsiveness and acceptability, on patients attending a primary care musculoskeletal clinic. One question was discarded from all three sets of questionnaires and a further question was removed from the neck questionnaire. Baseline scores approximated to normal distributions. Although not completely reproducible, they were internally consistent, so showed evidence of reliability. They were highly correlated with the SF-12 and their mean scores changed according to whether their health status, measured by a transition question, improved, stayed the same or worsened. Modified standardised response means showed large changes when health status improved and moderate-sized changes when health status worsened. Patients made few adverse comments about the questionnaires and found them acceptable. The Extended Aberdeen Spine Pain Scales for neck, upper and lower back pain, showed evidence of reliability, validity, responsiveness and acceptability. They can be used for single regions of the spine or combined as clinically necessary. They are particularly recommended for primary care patients.

Adult↗

PubMed2001

Monoaminergic innervation of the macaque extended amygdala.

The extended amygdala is a group of structures including the central and medial amygdaloid nuclei, bed nucleus of the stria terminalis, and sublenticular substantia innominata. This group of structures is thought to be important in a variety of psychiatric disorders, many of which are linked in one way or another to monoamines and their transporters. However, not much is known about the distribution of these molecules in the primate extended amygdala. Thus, we mapped the distribution of fibers immunoreactive for tyrosine hydroxylase, dopamine beta-hydroxylase, serotonin, dopamine transporter, and serotonin transporter in the brains of macaque monkeys. Tyrosine hydroxylase-, serotonin-, and serotonin transporter-immunoreactive fibers were found in highest concentrations in the lateral division of the central nucleus and lateral dorsal part of the bed nucleus of the stria terminalis. Dopamine beta-hydroxylase-immunoreactive fibers were found in the highest concentration in the lateral ventral bed nucleus of the stria terminalis. Dopamine transporter-immunoreactive fibers were found in the highest concentrations in the lateral juxtacapsular and lateral dorsal capsular subnuclei of the bed nucleus and lateral capsular subnucleus of the central amygdaloid nucleus, though in much lower amounts than was present in the striatum. These results suggest prominent roles for these transmitters, particularly in the lateral dorsal bed nucleus and lateral part of the central nucleus. The relative absence of dopamine transporter in the extended amygdala suggests that this transmitter acts more through volume transmission while serotonin, which is generally accompanied by proportionate amounts of transporter, may act more like a classical neurotransmitter. In addition, the finding of heavy concentrations of dopamine- and serotonin-immunoreactive fibers in the lateral central nucleus and lateral dorsal bed nucleus lends further support to the idea of these areas as parallels in some respects to the striatum.

Acetylcholine↗

PubMed1997

The use of tertiary collimation for spinal irradiation with extended SSD electron fields.

PURPOSE: The spine can be treated with an electron beam when its maximum posterior depth is within the therapeutic range of electrons. Electron fields treated at extended source-to-surface distances (SSDs), however, have larger penumbras and narrower therapeutic isodose widths relative to those at the standard SSD of 100 cm. We investigated the use of tertiary collimation close to the patient surface for these fields to sharpen the penumbra, minimizing dose to normal tissue and maximizing target coverage. METHODS AND MATERIALS: Using film dosimetry in a polystyrene phantom, we measured the dose distribution for electron fields at extended SSD under varying collimation conditions. Beam penumbra and therapeutic width as a function of depth, SSD, applicator insert size, and tertiary collimator opening were determined. We also measured the dose distributions in the junction region for various gaps between x-ray fields and an electron field as used for craniospinal irradiation. RESULTS: Measurements show that tertiary collimation close to the skin surface reduces penumbra width (lateral distance between the 90 and 20% isodose lines) by 56% and increases therapeutic isodose width (lateral width of the 90% isodose curve) by 25% at a depth of dmax relative to standard collimation. These numbers change to 23 and 13%, respectively, at an average depth of the spine. When lateral brain and posterior spine fields are used to irradiate the entire craniospinal axis, tertiary collimation aids in reducing the volume of the hot spot in the junction region by as much as 10% without compromising target coverage. CONCLUSIONS: Tertiary collimation for extended SSD electron fields is preferable to standard collimation in order to minimize dose to normal tissue and increase target coverage. This technique can be applied to both spinal and craniospinal irradiation. Support structures for the tertiary blocking are needed because the weight of the lead is usually too great for placement on the skin.

Electrons↗

PubMed2003

Novel Y-STR typing strategies reveal the genetic profile of the semen donor in extended interval post-coital cervicovaginal samples.

For a variety of reasons, some victims of sexual assault provide vaginal samples more than 24-36 h after the incident. In these cases, the ability to obtain an autosomal STR profile of the semen donor from the living victim diminishes rapidly as the post-coital interval is extended. We have used a number of carefully selected Y-STR loci in a variety of multiplex or monoplex formats to extend the post-coital interval from which a genetic profile of the semen donor can be obtained. The proposed Y-STR typing strategies enable the routine detection of the male donor Y-STR haplotype in cervicovaginal samples recovered up to 4 days post-coitus. We attribute our success to a number of factors that significantly improve the sensitivity and specificity of the analysis. Firstly, we utilize a subset of Y-STR loci that have been carefully selected for their superior performance under stressed conditions in both multiplex and monoplex formats. Specifically these loci function with low copy number templates in the presence of a vast excess of potentially confounding female DNA. Secondly, sperm and non-sperm DNA is co-extracted without a differential extraction process to prevent the unnecessary loss of the small number of structurally fragile sperm remaining in the cervicovaginal tract several days after intercourse. Thirdly, low copy number detection is facilitated by increasing the cycle number to 34-35 cycles and by the ability to input up to 450 ng of co-extracted sperm/non-sperm DNA into the PCR reaction without the appearance of confounding female artifacts. Lastly, the proper collection of post-coital cervicovaginal samples, instead of the lower or mid-vaginal tract samples often taken, is required for optimal recovery of sperm for analysis. In this report we demonstrate that our previously described 19 Y-STR loci systems (MPI and MPII) permit a reliable high resolution haplotype determination of the semen donor in cervicovaginal samples taken up to 48 h after intercourse. However, as the post-coital interval is extended further, dramatic loss of signal is observed and haplotype determination of the male donor is no longer possible with MPI and MPII. Nonetheless, subsets of these 19 loci (MPA and MPB) have been developed specifically to detect the male haplotype in samples recovered 4 days after intercourse. Thus, it is possible to derive an 11-19 locus Y-STR profile of the semen donor in cervicovaginal samples recovered 2-4 days after intercourse.

Chromosomes, Human, Y↗

PubMed1997

In-vivo/in-vitro correlation of four extended release formulations of pseudoephedrine sulfate.

An in-vivo/in-vitro correlation was established for four formulations of pseudoephedrine sulfate modified release tablets exhibiting different in-vivo and in-vitro release rate and absorption characteristics. In-vitro release rate data were obtained for 12 individual tablets of each formulation using the USP Apparatus 2 paddle stirrer at 50 rev min-1 in 1000 ml 0.1 N hydrochloric acid for the first hour followed by 0.1 M phosphate buffer at pH 7.5 for hours 2-16. Inspection of the individual and mean release rate data indicated that the in-vitro release rate of pseudoephedrine sulfate was consistent with the intended design of the four extended release formulations. The in-vivo bioavailability and pharmacokinetics of these formulations were evaluated in 20 healthy volunteers under fasted conditions. Wagner-Nelson analyses of the in-vivo data revealed extended release absorption profiles for all four formulations. Linear regression analyses of the mean percentage of dose absorbed versus the mean in-vitro release resulted in statistically significant correlations (r2 > 0.99, p < 0.0001) for each formulation. Qualitative rank order correlations were observed among all combinations of in-vivo and in-vitro parameters. These data support a Level A correlation between in-vivo absorption profiles and in-vitro release rates of four pseudoephedrine sulfate extended release formulations determined in fasted healthy volunteers.

Adult↗

PubMed1997

Glenoid-labral cyst entrapping the suprascapular nerve: dissolution after arthroscopic debridement of an extended SLAP lesion.

Glenoid labral cysts are commonly associated with labral tears, which can cause pain or instability. We present the case of a patient, referred for neurological complaints, who was actually suffering from supraspinatus nerve entrapment syndrome. Electroneurogram studies showed an isolated lesion of the branch to the infraspinatus muscle. Magnetic resonance imaging confirmed a glenoid labral cyst extending from the cranial glenoid to the scapular notch. After arthroscopic debridement of an extended SLAP-lesion that had caused joint fluid extrusion, the dissolution of the cyst was associated with complete neurological recovery. The patient is pain free and range of motion is normal. An attempt at an arthroscopic procedure seems warranted in cases like this, since cysts that accompany labral tears can dissolve after rigorous debridement of the torn labrum, much like meniscal cysts. Extended and hazardous open excisions can thus be avoided.

Arthralgia↗

PubMed2002

Steady-state pharmacokinetic comparison of a new, extended-release, once-daily morphine formulation, Avinza, and a twice-daily controlled-release morphine formulation in patients with chronic moderate-to-severe pain.

Extended-release morphine formulations are widely used in the management of chronic pain. Avinza (morphine sulfate extended-release [MSER, Morphelan]) is a new, once-a-day, extended-release morphine formulation designed to reach target concentrations rapidly and maintain concentrations throughout a 24-hour period. The primary objective of this study was to compare the 24-hour steady-state pharmacokinetic (PK) profiles of morphine and its metabolites (morphine-6-glucuronide [M6G] and morphine-3-glucuronide [M3G]) following ingestion of MSER once-a-day and MS Contin (controlled-release morphine sulfate [CRM]) twice-a-day in patients with chronic moderate-to-severe pain. Ten patients with chronic moderate-to-severe pain were recruited into an open-label, multiple-dose, nonrandomized, two-period, single-center study. All patients were stabilized for a minimum of 7 days on a twice-daily dose of CRM associated with an optimal balance between pain control and side effects. Patients were then switched to the closest equivalent once-daily dose of MSER for a minimum of 10 days. Twenty-four hour steady-state PK profiles were obtained on the last day of each treatment period and additional clinical and safety assessments were performed. PK data were normalized to a 100-mg total daily dose prior to statistical analysis. Nine of the 10 patients completed the entire study. MSER and CRM demonstrated similar bioavailability (AUC) of morphine and its metabolites. Compared to CRM, MSER demonstrated a 19% lower maximum concentration (C(max)), a 66% higher minimum concentration (C(min)), and a 44% lower peak-to-trough fluctuation (%FI) over the 24-hour period. In addition, MSER maintained concentrations above 50% and 75% of the C(max) longer than CRM. Clinical efficacy and safety were comparable for MSER and CRM. Once-daily MSER approaches maximum morphine concentration more quickly, approximates maximum concentration longer, and demonstrates less fluctuation in morphine concentration during a 24-hour period than CRM dosed twice daily. The pharmacodynamic implications of this profile deserve further study.

Adult↗

PubMed2002

Retinal ganglion cells do not extend axons by default: promotion by neurotrophic signaling and electrical activity.

We investigate the signaling mechanisms that induce retinal ganglion cell (RGC) axon elongation by asking whether surviving neurons extend axons by default. We show that bcl-2 overexpression is sufficient to keep purified RGCs alive in the absence of any glial or trophic support. The bcl-2-expressing RGCs do not extend axons or dendrites unless signaled to do so by single peptide trophic factors. Axon growth stimulated by peptide trophic factors is remarkably slow but is profoundly potentiated by physiological levels of electrical activity spontaneously generated within embryonic explants or mimicked on a multielectrode silicon chip. These findings demonstrate that these surviving neurons do not constitutively extend axons and provide insight into the signals that may be necessary to promote CNS regeneration.

Animals↗

PubMedDate not supplied

Beta-lactamase-mediated resistance to extended spectrum cephalosporins among clinical isolates of Pseudomonas aeruginosa.

The role of chromosomal cephalosporinases and secondary beta-lactamases in resistance to extended spectrum cephalosporins in clinical isolates of Pseudomonas aeruginosa was investigated. Strains 687, 59, and 58 expressed an inducible chromosomal cephalosporinase, efficiently enhanced with cefoxitin and imipenem. The inducible activity in strain 802 was produced at a moderately elevated basal level and may be involved in resistance to extended spectrum cephalosporins and aztreonam. All strains produced secondary beta-lactamases inhibited by clavulanate: strains 687, 59, and 58 had carbenicillinases with pIs of 5.7 and 5.3. Strain 802 expressed a secondary beta-lactamase of pI 7.6 which may be a novel extended spectrum beta-lactamase different from known enzymes of P. aeruginosa.

Cefotaxime↗

PubMed1998

Effects of extended preoperative information on perioperative stress: an anaesthetic nurse intervention for patients with breast cancer and total hip replacement.

An anaesthetic nurse intervention was performed in order to evaluate the effects of extended preoperative information, given by anaesthetic nurses, on perioperative stress in patients operated on for breast cancer or total hip replacement (THR). Forty-six consecutive patients scheduled for surgery for breast cancer, and 55 for THR, were randomized into two groups which were given different modes of preoperative information. Patients in the control group were informed about pre- and postoperative routines by a ward nurse. Patients in the intervention group were given extended formalized information by an anaesthetic nurse. Wilcoxon rank sum test was used to show relations between variables. There were no significant differences between the intervention group and control group for patients with breast cancer or for patients with THR. Breast cancer patients in the intervention group were significantly more anxious than THR patients in the intervention group (P < 0.01). Breast cancer patients in the intervention group showed the highest anxiety scores on the Hospital Anxiety and Depression Scale (HADS) scale on the day of surgery. This information may reflect an increased level of anxiety due to the extended information given preoperatively. The information may thus have had a negative effect on breast cancer patients, resulting in an increased state of anxiety. The result indicates a need for individualized modes of information to provide a proper balance between enough and too much information.

Aged↗

PubMed2001

On the extended depth of focus algorithms for bright field microscopy.

Microscopes offer a limited depth of focus which precludes the observation of a complete image of a three-dimensional (3D) object in a single view. Investigations, by a variety of researchers, have led to the development of extended depth of focus algorithms for serial optical slices of microscopic 3D objects in recent years. However, to date, no quantitative comparison of the different algorithms has been performed, generally leaving the evaluation to the subjective qualitative appreciation of the observer. In this paper we use three different tests for extended depth of focus algorithm evaluation and test 10 different algorithms, some of them have been adapted (by us) for a series of optical slices. However, the main contribution of the paper is a new improved algorithm for computing the extended depth of focus.

Algorithms↗

PubMed2002

Appearance of thymoma 15 years after extended thymectomy for myasthenia gravis without thymoma.

Several cases of thymoma recurrence after resection have been reported. However, thymoma appearance following an extended thymectomy for non-thymomatous myasthenia gravis is very rare. We report a case of thymoma in a 48-year-old woman, 15 years after an extended thymectomy for non-thymomatous myasthenia gravis. The importance of a complete dissection of mediastinal adipose tissue during the extended thymectomy as well as careful follow-up for such patients is also noted.

Female↗

PubMed2003

Subtotal esophagectomy with extended 2-field lymph node dissection for thoracic esophageal cancer.

OBJECTIVE: To examine the efficacy of the Ivor Lewis esophagectomy with extended 2-field lymph node dissection for thoracic esophageal carcinoma we reviewed our experience. METHODS: We analyzed the cases of 147 consecutive patients who underwent subtotal esophagectomy with extended 2-field lymph node dissection through Ivor Lewis approach for esophageal cancer from January 1996 through December 2000. Eighty-six patients were operated on for cancer of the midthoracic esophagus, 48 for cancer of the lower thoracic esophagus, and 13 for cancer of the aortal segment of the esophagus. No patient had received chemotherapy or radiotherapy before operation. RESULTS: There were 113 men (76.9%) and 34 women. Median age was 57 years (range 51-65 years). Postsurgical pathological studies revealed squamous cell carcinoma in 139 patients (94.6%), adenocarcinoma in five (3.4%), and adenosquamous carcinoma in three (2%). Positive abdominal and/or mediastinal lymph nodes were found in 122 patients (82.9%). At mean 43 nodes (range from 32 up to 75) were studied for each patient. Even in T(1)-T(2) tumors mediastinal or abdominal lymph nodes are involved in up to 80% of cases. However, in T(3)-T(4) stages the frequency of lymph node involvement is significantly higher (P<0.05). Postsurgical staging was as follows: stage I in three patients (2%), stage IIa in 20 (13.6%), stage IIb in 29 (19.7%), stage III in 54 (36.8%), and stage IV in 41 (27.9%). All distant metastases were lymphogenous. The operative mortality rate was 6.1%, and complications occurred in 62 patients (42.1%). The overall 5-year survive rate was 28.8% (median survival 36.1 months). The 5-year survival rate for patients in stage IIa was 59%; for those in stage IIb, 39.5%; for patients in stage III, 26.7%; and 0% for patients in stage IV. CONCLUSIONS: Subtotal esophagectomy with extended 2-field lymph node dissection through Ivor Lewis approach for esophageal cancer is a safe operation. Long-term survival is stage dependent. Effective multimodality treatment may be helpful for patients with advanced disease.

Adenocarcinoma↗

PubMed1997

In vivo measurement of lung preservation solution efficacy: comparison of LPD, UW, EC and low K+-EC following short and extended ischemia.

OBJECTIVE: The impact of storage solution composition on graft performance was evaluated following perfusion with either Euro-Collins (EC), low potassium Euro-Collins (rEC), low potassium dextran (LPD) or University of Wisconsin solution (UW) after brief (2 h) and extended ischemia (16 h) in an acute double lung transplantation model in the rat. METHODS: Following flush perfusion and ischemia the lungs were implanted in recipient rats allowing serial assessment of graft pulmonary vascular resistance (PVR) and alveolar arterial oxygen difference (AaDO2) during 120 min of reperfusion. Graft dynamic lung compliance (DLC) was determined by separate ventilation. Final evaluation included weight gain and histology. RESULTS: After extended ischemia LPD provided superior graft function in respect to DLC (repeated measures ANOVA; LPD versus rEC P < 0.05; versus EC P < 0.03; versus UW P < 0.05) and AaDO2 (LPD versus rEC P < 0.04; versus EC P < 0.006). The PVR was significantly lower in LPD versus UW (P < 0.05). At the end of reperfusion the weight increase amounted to 229 +/- 49% in rEC, 207 +/- 22% in EC, 115 +/- 22% in UW and 87 + 17% in LPD (LPD versus rEC P < 0.01, LPD versus EC P < 0.001). The type of preservation solution used had little impact on graft function after 2 h ischemia. CONCLUSIONS: Low potassium dextran provides superior graft function after extended ischemia. After short ischemia the type of preservation solution used in this study had little impact on global lung function.

Adenosine↗

PubMed1999

Total gastrectomy with extended lymphadenectomy for "curable" stomach cancer: experience in a non-Japanese Asian center.

BACKGROUND: Gastrectomy with extended lymphadenectomy is the advocated treatment in Japan for patients with "curable" stomach cancer. Attempts in units elsewhere adopting this approach failed to show any survival advantage, and the high operative mortality has prevented global acceptance of the operation. This study examines the safety and efficacy of radical gastrectomy in a Far East center outside Japan. STUDY DESIGN: A consecutive series of 121 patients with gastric cancer who fulfilled criteria for radical surgery had total gastrectomy with extended lymphadenectomy equivalent to D3 dissection over a 6-year period in a single unit. RESULTS: The operation carried a morbidity of 50%, with a perioperative mortality of 5%. Survival was best predicted by tumor stage: 5-year survival for patients with intact gastric serosa was 64%, versus 10% for those with serosal penetration (p < 0.001). The majority of documented metastases occurred by transperitoneal route in serosa-positive patients, but via the hematogenous mechanisms in those who were serosa-negative. CONCLUSIONS: Radical gastrectomy with extended lymphadenectomy carries high operative morbidity. Increased mortality occurred because of loco-regional recurrence in patients with T3/T4 diseases. Novel approaches including neoadjuvant treatment or regional therapy should be explored.

Adenocarcinoma↗

PubMed2003

Extended-term cultures of human T-lymphocytes and the comet assay: a useful combination when testing for genotoxicity in vitro?

Extended-term cultures of human lymphocytes provide a source of uniform human cells that can be used for several experiments performed over a long time, avoiding the variability arising from taking blood samples for individual experiments. The use of extended-term cultures of human T-lymphocytes in the alkaline single-cell gel electrophoresis assay (comet assay) was evaluated as a test for the potential genotoxicity of chemicals. The DNA-damaging effects of five DNA-reactive mutagens and clastogens (benzo[a]pyrene, cyclophosphamide, formaldehyde, 4-nitroquinoline-N-oxide (4NQO) and N-nitrosopiperidine) was determined and compared with the effects of one non-DNA-reactive mutagen (5-hydroxyurea), and one non-mutagenic agent (ethanol). The alkylating and/or DNA-adduct forming agents N-nitrosopiperidine, cyclophosphamide, 4-nitroquinoline-N-oxide and benzo[a]pyrene increased the DNA migration in a dose-dependent manner. In contrast, the DNA/protein-crosslinking agent formaldehyde decreased the migration of DNA during the electrophoresis. The lowest observed effect levels (LOELs) under the experimental conditions used in the present study, were: 0.0001 mM (4-nitroquinoline-N-oxide without S9), 0.05 mM (benzo[a]pyrene with S9), 0.1mM (formaldehyde without S9), 0.25 mM (cyclophosphamide with S9), and 0.5mM (N-nitrosopiperidine with S9), respectively. The antimetabolite 5-hydroxyurea was also found to increase the tail moment, but only in cells that had been exposed to rather high concentrations (> or =10mM) of the compound. Ethanol did not affect the tail moment, not even in cells that had been exposed to an apparently cytotoxic concentration (500 mM). The results of the present study are in qualitative agreement with those obtained using other cells in the alkaline comet assay and it is therefore concluded that extended-term cultures of human T-lymphocytes and the alkaline version of the single-cell gel electrophoresis assay is a useful combination when testing for the potential genotoxicity of chemicals.

Adult↗

PubMed2005

Value of extended recording time with wireless pH monitoring in evaluating gastroesophageal reflux disease.

BACKGROUND & AIMS: Extending an ambulatory pH study by using a wireless capsule system could improve diagnosis of gastroesophageal reflux disease in patients with symptoms potentially related to acid reflux events. We determined the relative value of a 2-day versus a 1-day study in detection of abnormal esophageal acid exposure and reflux symptom associations. METHODS: Subjects who had undergone pH monitoring with the wireless system for symptom evaluation and who had at least 1 typical or atypical symptom during monitoring were studied (n = 157). Acid exposure time, symptom index, and a measure of reflux-associated symptom probability were calculated after 1 day of recording and compared to final results from analysis of 2 days of data. RESULTS: Extending recording time increased the number of subjects recording symptoms by 6.8% and doubled the number of symptoms available for association with acid reflux events. Other advantages were greater in subjects off antireflux therapy, wherein lengthening recording time increased the proportion of subjects with abnormal acid exposure time by 12.4% and significantly increased the likelihood of a positive reflux symptom relationship in subjects with atypical symptoms. Accuracy of a 1-day study ranged from 0.87-0.88 for acid exposure time to as low as 0.72-0.87 for the probability test, the most sensitive of the symptom association tests. CONCLUSIONS: Extending recording time to 2 days with the wireless pH monitoring system increases the likelihood of detecting reflux disease in patients undergoing symptom evaluation. Benefits are most evident for subjects with atypical symptoms and for establishing reflux symptom associations by probability testing.

Adult↗

PubMed2006

Do age and extended culture affect the architecture of the zona pellucida of human oocytes and embryos?

Advanced female age and extended in vitro culture have both been implicated in zona pellucida (ZP) hardening and thickening. This study aimed to determine the influence of (i) the woman's age and (ii) prolonged in vitro culture of embryos on ZP thickness and density using non-invasive polarized light (LC-PolScope) microscopy. ZP thickness and density (measured as retardance) were determined in oocytes, embryos and blastocysts in women undergoing intracytoplasmic sperm injection (ICSI) in two age groups (older, > 38 years; younger, < or = 38 years). A total of 193 oocytes from 29 patients were studied. The younger group contained 100 oocytes and the older group 93 oocytes. The ZP was significantly thicker in metaphase II oocytes in the older group compared with the younger group (mean +/- SD: 24.1 +/- 2.5 microm vs 23.1 +/- 3.3 microm; p = 0.01) but ZP density was equal (2.8 +/- 0.7 nm). By day 2 of culture, embryos from the two groups had similar ZP thickness (22.2 +/- 2.2 microm vs 21.7 +/- 1.6 microm; p = 0.28) and density (2.9 +/- 0.7 nm vs 2.8 +/- 0.8 nm; p = 0.57). For the embryos cultured to blastocyst (older: n = 20; younger: n = 18) ZP thickness was similar in the two groups (19.2 +/- 2.7 microm vs 19.1 +/- 5.0 microm; p = 0.8) but thinner than on day 2. The older group had significantly denser ZP than the younger group (4.2 +/- 0.5 nm vs 3.3 +/- 1.0 nm, p < 0.01). Blastocysts from both groups had significantly denser ZP than their corresponding day 2 embryos (older: 4.2 +/- 0.5 nm vs 2.9 +/- 0.7 nm, p < 0.001; younger: 3.3 +/- 1.0 nm vs 2.8 +/- 0.8 nm, p = 0.013). It is concluded that there is little relationship between ZP thickness and its density as measured by polarized light microscopy. While ZP thickness decreases with extended embryo culturing, the density of the ZP increases. ZP density increases in both age groups with extended culture and, interestingly, more in embryos from older compared with younger women.

Adult↗