The desired properties required for successful embalming of cadavers for gross anatomy teaching include: (1) good long‐term structural preservation of organs and tissues with minimal shrinkage or distortion; (2) prevention of over‐hardening, while maintaining flexibility and suppleness of internal organs; (3) prevention of desiccation; (4) prevention of fungal or bacterial growth and spread within a specific cadaver and to other cadavers in the dissection room; (5) reduction of potential biohazards (spread of infection to dissection personnel and students); (6) reduction of environmental chemical hazards (especially from formaldehyde and phenol) in order to comply with increasingly severe health and safety regulations and a new awareness of possible dangers of these chemicals in the workplace; and (7) retention of colour of tissues and organs while minimising oxidation effects that result in ‘browning’.
SPECT/CT affected the diagnostic interpretation of SRS in 32% of the patients and induced changes in management in 14% of the patients.
The aim of this study was to determine the accuracy of multidetector row CT angiography in the diagnosis of acute mesenteric ischemia. Ninety-three consecutive studies on 91 patients with clinically suspected acute mesenteric ischemia underwent abdominal CT angiography as the first, and usually the sole, diagnostic procedure. CT was performed with a multidetector 16-row CT system from the level of the diaphragm to the pelvis in two phases: early arterial and late portal phase. CT examinations were reviewed by the duty radiologist. Final diagnosis was established by a senior radiologist. CTA was diagnostic in 92 studies. Mesenteric ischemia was diagnosed in 18 patients, 14 of them were of the thromboembolic type and four from the nonocclusive type. Positive CTA findings were confirmed by surgery in 13 patients and by clinical follow-up in three cases. Other reasons for abdominal pain were diagnosed by CT in 38 patients out of the remaining 74. There were two false positive and two false negative CT results, resulting in an overall accuracy of 95.6%. Multidetector CT angiography is a fast and accurate investigation for the diagnosis of acute mesenteric ischemia and in most cases can be used as the sole diagnostic procedure.
We report the sequential changes in 5-hydroxymethylcytosine (5hmC) patterns in the genome of human preimplantation embryos during DNA methylation reprogramming. We have studied chromosome hydroxymethylation and methylation patterns in triploid zygotes and blastomeres of cleavage-stage embryos. Using indirect immunofluorescence, we have analyzed the localization of 5hmC and its co-distribution with 5-methylcytosine (5mC) on the QFH-banded metaphase chromosomes. In zygotes, 5hmC accumulates in both parental chromosome sets, but hydroxymethylation is more intensive in the poorly methylated paternal set. In the maternal set, chromosomes are highly methylated, but contain little 5hmC. Hydroxymethylation is highly region specific in both parental chromosome sets: hydroxymethylated loci correspond to R-bands, but not G-bands, and have well-defined borders, which coincide with the R/G-band boundaries. The centromeric regions and heterochromatin at 1q12, 9q12, 16q11.2, and Yq12 contain little 5mC and no 5hmC. We hypothesize that 5hmC may mark structural/functional genome 'units' corresponding to chromosome bands in the newly formed zygotic genome. In addition, we suggest that the hydroxymethylation of R-bands in zygotes can be treated as a new characteristic distinguishing them from G-bands. At cleavages, chromosomes with asymmetrical hydroxymethylation of sister chromatids appear. They decrease in number during cleavages, whereas totally non-hydroxymethylated chromosomes become numerous. Taken together, our findings suggest that, in the zygotic genome, 5hmC is distributed selectively and its pattern is determined by both parental origin of chromosomes and type of chromosome bands -R, G, or C. At cleavages, chromosome hydroxymethylation pattern is dynamically changed due to passive and non-selective overall loss of 5hmC, which coincides with that of 5mC.
Background: Severe forms of genital endometriosis are known to be associated with infertility and its subsequent treatment failure. Both gonadotropin-releasing hormone analogs (a-GnRH) and dienogest have been suggested as additional hormone therapy for patients with endometriomas. However, the result of hormonal suppression before an in vitro fertilization (IVF) cycle remains undetermined. Materials and methods: A prospective cohort study of 144 infertile women planning IVF after laparoscopic surgery of ovarian endometriomas was conducted at our department in 2012-2015. Patients were divided into three groups: group I (N ¼ 38) with dienogest course, group II (N ¼ 70) with a-GnRH group III (N ¼ 70) without any hormonal therapy within 6 months preceding IVF. Results: The study groups did not differ by removed endometriomas size and ovarian reserve indicators. The gonadotropin dose per Cycle was higher, while the number of retrieved oocytes was lower in group III patients (p < .001). In women with dienogest pretreatment, clinical pregnancy rate was 2.5 times (44.7% versus 16.7%, p ¼ .012) and delivery rate -three times higher (36.8% versus 11.1%, p ¼ .013) as compared with those from group III. Conclusions: The present study confirms the necessity of pre-cycle medical interventions in women with ovarian forms of endometriosis undergoing IVF. We suggest dienogest to be possibly more efficient treatment option for this kind of patients.
Background: Ectopic pregnancy (EP) has been reported to occur in 1.4-5.4% of all clinical pregnancies resulting from in vitro fertilization (IVF) and embryo transfer (ET). Data on factors associated with abnormal embryo implantation following assisted conception are limited. Materials and methods: A systematic review and meta-analysis was performed to determine whether there is an association between the day (cleavage-stage, D3, versus blastocyst, D5) or the type (fresh versus frozen/thawed) of ET and EP rate. Risk factors for EP were evaluated in a retrospective study of 1194 women, who achieved pregnancy at our IVF unit between 2010 and 2016. Results: Sixteen papers were considered for the meta-analysis. EP rate did not differ between D3 and D5 fresh ET groups (RR ¼ 0.99, 95%CI: 0.76-1.30) and was higher after fresh versus frozen ET (RR ¼ 1.56, 95%CI: 1.25-1.95). At our clinic, 21 (1.76%) pregnancies were documented as ectopic. The risk of EP was associated with tubal pathology (OR ¼ 3.37, 95%CI: 1.39-8.2), previous appendectomy and past chlamydial infection. Conclusions: Present meta-analysis suggests that EP rate is similar following fresh blastocyst and cleavage ETs, but is significantly reduced after frozen compared with fresh ET. Our own findings demonstrate that tubal pathology has the major impact on EP occurrence following assisted conception.
We performed immunofluorescent analysis of DNA hydroxymethylation and methylation in human testicular spermatogenic cells from azoospermic patients and ejaculated spermatozoa from sperm donors and patients from infertile couples. In contrast to methylation which was present throughout spermatogenesis, hydroxymethylation was either high or almost undetectable in both spermatogenic cells and ejaculated spermatozoa. On testicular cytogenetic preparations, 5-hydroxymethylcytosine was undetectable in mitotic and meiotic chromosomes, and was present exclusively in interphase spermatogonia Ad and in a minor spermatid population. The proportions of hydroxymethylated and non-hydroxymethylated diploid and haploid nuclei were similar among samples, suggesting that the observed alterations of 5-hydroxymethylcytosine patterns in differentiating spermatogenic cells are programmed. In ejaculates, a few spermatozoa had high 5-hydroxymethylcytosine level, while in the other ones hydroxymethylation was almost undetectable. The percentage of highly hydroxymethylated (5-hydroxymethylcytosine-positive) spermatozoa varied strongly among individuals. In patients from infertile couples, it was higher than in sperm donors (P<0.0001) and varied in a wider range: 0.12-21.24% versus 0.02-0.46%. The percentage of highly hydroxymethylated spermatozoa correlated strongly negatively with the indicators of good semen quality – normal morphology (r=-0.567, P<0.0001) and normal head morphology (r=-0.609, P<0.0001) – and strongly positively with the indicator of poor semen quality: sperm DNA fragmentation (r=0.46, P=0.001). Thus, the immunocytochemically detected increase of 5hmC in individual spermatozoa is associated with infertility in a couple and with deterioration of sperm parameters. We hypothesize that this increase is not programmed, but represents an induced abnormality and, therefore, it can be potentially used as a novel indicator of semen quality.
To estimate the efficacy of growth hormone (GH) co-treatment within an antagonist protocol in IVF/ICSI cycles in poor responders. A prospective observational study involving 50 patients underwent a standard antagonist protocol with or without GH co-treatment. GH was administered by a daily subcutaneous injection of 1,33 mg (equivalent to 4 IU) starting from day 1 of ovarian stimulation until the day of 10,000 human chorionic gonadotropin (hCG) triggering . Concentrations of GH, insulin-like growth factor I (IGF-I) and IGF binding protein-3 (IGFBP-3) in serum and follicular fluid were the subject matter of analysis. The GH co-treatment significantly lowered the effective dose of gonadotropins, duration of stimulation, IGFBP-3 level in serum and follicular fluid on the day of oocyte retrieval. The total number of oocytes as well as the number of metaphase II stage (MII) oocytes, two pronucleus (2 pn) zygotes, good-quality transferred embryos was significantly higher in the GH þ group. Pregnancy was achieved in patients GH þ group only. Positive correlation was found between IGF-I level in follicular fluid, dynamics of IGFBP-3 level changes during stimulation protocol and the number of good-quality transferred embryos in the GH þ group. GH administration in IVF/ICSI cycles for poor responders raises ovarian sensitivity to the gonadotropin exogenous influence, increasing number of high-quality embryos and the probability of pregnancy. ARTICLE HISTORY
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