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1.
Metabolites ; 13(7)2023 Jun 21.
Article in English | MEDLINE | ID: mdl-37512482

ABSTRACT

The hormonal form of vitamin D3, 1,25(OH)2D3, reduces UV-induced DNA damage. UV exposure initiates pre-vitamin D3 production in the skin, and continued UV exposure photoisomerizes pre-vitamin D3 to produce "over-irradiation products" such as lumisterol3 (L3). Cytochrome P450 side-chain cleavage enzyme (CYP11A1) in skin catalyzes the conversion of L3 to produce three main derivatives: 24-hydroxy-L3 [24(OH)L3], 22-hydroxy-L3 [22(OH)L3], and 20,22-dihydroxy-L3 [20,22(OH)L3]. The current study investigated the photoprotective properties of the major over-irradiation metabolite, 24(OH)L3, in human primary keratinocytes and human skin explants. The results indicated that treatment immediately after UV with either 24(OH)L3 or 1,25(OH)2D3 reduced UV-induced cyclobutane pyrimidine dimers and oxidative DNA damage, with similar concentration response curves in keratinocytes, although in skin explants, 1,25(OH)2D3 was more potent. The reductions in DNA damage by both compounds were, at least in part, the result of increased DNA repair through increased energy availability via increased glycolysis, as well as increased DNA damage recognition proteins in the nucleotide excision repair pathway. Reductions in UV-induced DNA photolesions by either compound occurred in the presence of lower reactive oxygen species. The results indicated that under in vitro and ex vivo conditions, 24(OH)L3 provided photoprotection against UV damage similar to that of 1,25(OH)2D3.

3.
Hum Fertil (Camb) ; 26(5): 1334-1339, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36942480

ABSTRACT

Haemoglobinopathies are among the most common inherited disorders around the world. In the United States the diagnosis of haemoglobinopathy or a carrier state is made by universal newborn screening. However, many individuals of childbearing age do not know they are a haemoglobinopathy carrier. Screening for common haemoglobinopathies is generally offered as a part of pregnancy planning so that prospective parents can be counselled regarding the risk of having a child with a haemoglobinopathy. Multiple tests exist to screen patients for presence of haemoglobinopathy carrier or disease state; however, it is crucial to order and interpret the results correctly to appropriately counsel couples. In this case series, we describe clinical scenarios where prospective parents were surprised to unexpectedly have a child with sickle cell disease, a haemoglobinopathy that causes severe clinical complications. Through these cases we demonstrate that deficiencies in testing can occur at different levels which may lead to incorrect estimation of the risk of having a child affected by a haemoglobinopathy. Consultation with a haematologist, laboratory medicine specialist, or genetic counsellor should be considered to select the appropriate test and interpret its results.


Subject(s)
Anemia, Sickle Cell , Hemoglobinopathies , Female , Humans , Pregnancy , Anemia, Sickle Cell/complications , Anemia, Sickle Cell/diagnosis , Anemia, Sickle Cell/genetics , Hemoglobinopathies/diagnosis , Hemoglobinopathies/genetics , Prospective Studies
4.
J Clin Anesth ; 30: 35-41, 2016 May.
Article in English | MEDLINE | ID: mdl-27041261

ABSTRACT

STUDY OBJECTIVE: To evaluate intra-abdominal needle trajectories of the classic transcrural celiac plexus block (tCPB) with a simulation technique. DESIGN: Classic tCPB technique cited from 10 latest authoritative textbooks were simulated on abdominal computed tomography images retrospectively. SETTING: University-affiliated community hospital. MEASUREMENTS: One hundred axial computed tomography images across the celiac trunk were retrieved. Three lines simulating classic tCPB were executed on each image. The organs traversed by each line were noted and analyzed. The frequencies of organ traverse were compared with the incidences described in the literature. MAIN RESULTS: All 3 lines traversed various organs with different frequencies. The right side line frequently traversed the right kidney (36%). The left side line always traversed the aorta (100%). The modified line on the right side frequently traversed the inferior vena cava (32%). The highest kidney traverse percentage on both sides and the highest aorta traverse percentage on the right side were observed in pancreatic cancer patients. CONCLUSIONS: Despite uncommon clinical complications, classic tCPB needle placement frequently traversed through several key organs in this simulation series. Organ penetrations could be avoided by needle trajectory adjustment.


Subject(s)
Cervical Plexus Block/methods , Needles , Tomography, X-Ray Computed/methods , Adult , Aged , Cervical Plexus Block/adverse effects , Female , Humans , Male , Middle Aged , Pancreatic Neoplasms/pathology , Retrospective Studies
5.
Reprod Biol Endocrinol ; 12: 106, 2014 Nov 24.
Article in English | MEDLINE | ID: mdl-25420620

ABSTRACT

BACKGROUND: Flow cytometric sorting can be used to separate sperm based on sex chromosome content. Differential fluorescence emitted by stained X- vs. Y-chromosome-bearing sperm enables sorting and collection of samples enriched in either X- or Y-bearing sperm for use to influence the likelihood that the offspring will be a particular sex. Herein we report the effectiveness of flow cytometric sorting of human sperm and its use in human ART procedures. METHODS: This prospective, observational cohort study of the series of subjects treated with flow cytometrically sorted human sperm was conducted at investigational sites at two private reproductive centers. After meeting inclusion criteria, married couples (n = 4993) enrolled to reduce the likelihood of sex-linked or sex-limited disease in future children (n = 383) or to balance the sex ratio of their children (n = 4610). Fresh or frozen-thawed semen was processed and recovered sperm were stained with Hoechst 33342 and sorted by flow cytometry (n = 7718) to increase the percentage of X-bearing sperm (n = 5635) or Y-bearing sperm (n = 2083) in the sorted specimen. Sorted sperm were used for IUI (n = 4448) and IVF/ICSI (n = 2957). Measures of effectiveness were the percentage of X- and Y-bearing sperm in sorted samples, determined by fluorescence in situ hybridization, sex of babies born, IVF/ICSI fertilization- and cleavage rates, and IUI, IVF/ICSI, FET pregnancy rates and miscarriage rates. RESULTS: Sorted specimens averaged 87.7 ± 5.0% X-bearing sperm after sorting for X and 74.3 ± 7.0% Y-bearing sperm after sorting for Y. Seventy-three percent of sorts were for girls. For babies born, 93.5% were females and 85.3% were males after sorting for X- and Y-bearing sperm, respectively. IUI, IVF/ICSI, and FET clinical pregnancy rates were 14.7%, 30.8%, and 32.1%, respectively; clinical miscarriage rates were 15.5%, 10.2%, and 12.7%. CONCLUSIONS: Flow cytometric sorting of human sperm shifted the X:Y sperm ratio. IUI, IVF/ICSI and FET outcomes were consistent with unimpaired sperm function. Results provide evidence supporting the effectiveness of flow cytometric sorting of human sperm for use as a preconception method of influencing a baby's sex. TRIAL REGISTRATION: NCT00865735 (ClinicalTrials.gov).


Subject(s)
Cell Separation/methods , Flow Cytometry/methods , Sex Preselection/methods , Spermatozoa/cytology , Chromosomes, Human, X/genetics , Chromosomes, Human, Y/genetics , Female , Fertilization in Vitro , Humans , In Situ Hybridization, Fluorescence , Infant, Newborn , Insemination, Artificial , Male , Pregnancy , Pregnancy Outcome , Pregnancy Rate , Prospective Studies , Reproducibility of Results , Sex Ratio , Sperm Injections, Intracytoplasmic , Spermatozoa/metabolism
6.
Mol Cytogenet ; 7(1): 18, 2014 Feb 28.
Article in English | MEDLINE | ID: mdl-24581286

ABSTRACT

BACKGROUND: Most previous studies of chromosomal mosaicism in IVF embryos were performed by fluorescence in situ hybridization (FISH) methods. While there are reports implicating chromosome aneuploidy in implantation failure following transfer and pregnancy loss by spontaneous miscarriage, the significance of mosaicism for the developmental potential of growing embryos is unknown. However, the low prevalence of chromosomal mosaicism in chorionic villus sampling and amniotic fluid specimens suggests the presence of selection against mosaic embryos for implantation and early pregnancy. The absence of evidence for selective allocation of abnormal cells to the trophectoderm (TE) of mosaic blastocysts permits these cells to be a good proxy for embryonic mosaicism detection by chromosomal microarrays (CMA). The purpose of this study was to establish the limits of detection and the prevalence of chromosome mosaicism in day 5/6 human embryos using CMA with TE biopsies. RESULTS: From reconstitution experiments we established log2 ratio thresholds for mosaicism detection. These studies indicated that chromosomal mosaicism at levels as low as between 25-37% can be consistently identified. Follow-up studies by FISH on non-transferred abnormal embryos confirmed the diagnostic accuracy of CMA testing. The number of cells in a TE biopsy can influence mosaicism detection. CONCLUSIONS: Chromosomal microarrays can detect mosaicism in TE biopsies when present at levels as low as between 25-37% and the prevalence of day 5/6 blastocysts which were mosaic and had no other abnormalities reached 15% among a cohort of 551 embryos examined. Validated protocols for establishing detection thresholds for mosaicism are important to reduce the likelihood of transferring abnormal embryos.

8.
J Clin Med ; 3(1): 280-309, 2014 Mar 17.
Article in English | MEDLINE | ID: mdl-26237262

ABSTRACT

Preimplantation genetic diagnosis was developed nearly a quarter-century ago as an alternative form of prenatal diagnosis that is carried out on embryos. Initially offered for diagnosis in couples at-risk for single gene genetic disorders, such as cystic fibrosis, spinal muscular atrophy and Huntington disease, preimplantation genetic diagnosis (PGD) has most frequently been employed in assisted reproduction for detection of chromosome aneuploidy from advancing maternal age or structural chromosome rearrangements. Major improvements have been seen in PGD analysis with movement away from older, less effective technologies, such as fluorescence in situ hybridization (FISH), to newer molecular tools, such as DNA microarrays and next generation sequencing. Improved results have also started to be seen with decreasing use of Day 3 blastomere biopsy in favor of polar body or Day 5 trophectoderm biopsy. Discussions regarding the scientific, ethical, legal and social issues surrounding the use of sequence data from embryo biopsy have begun and must continue to avoid concern regarding eugenic or inappropriate use of this technology.

9.
J Steroid Biochem Mol Biol ; 136: 131-8, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23165145

ABSTRACT

Vitamin D production requires UVB. In turn, we have shown that vitamin D compounds reduce UV-induced damage, including inflammation, sunburn, thymine dimers, the most frequent type of cyclobutane pyrimidine dimer, immunosuppression, and photocarcinogenesis. Our previous studies have shown most of the photoprotective effects by 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) occurred through the nongenomic pathway because similar protection was seen with an analog, 1α,25-dihydroxylumistrol3 (JN), which has little ability to alter gene expression and also because a nongenomic antagonist of 1,25(OH)2D3 abolished protection. In the current study, we tested whether this photoprotective effect would extend to other types of DNA damage, and whether this could be demonstrated in human ex vivo skin, as this model would be suited to pre-clinical testing of topical formulations for photoprotection. In particular, using skin explants, we examined a time course for thymine dimers (TDs), the most abundant DNA photolesion, as well as 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), which is a mutagenic DNA base lesion arising from UV-induced oxidative stress, and 8-nitroguanosine (8-NG). Nitric oxide products, known markers for chronic inflammation and carcinogenesis, are also induced by UV. This study showed that 1,25(OH)2D3 significantly reduced TD and 8-NG as early as 30min post UV, and 8-oxodG at 3h post UV, confirming the photoprotective effect of 1,25(OH)2D3 against DNA photoproducts in human skin explants. At least in part, the mechanism of photoprotection by 1,25(OH)2D3 is likely to be through the reduction of reactive nitrogen species and the subsequent reduction in oxidative and nitrosative damage. This article is part of a Special Issue entitled 'Vitamin D Workshop'.


Subject(s)
Calcitriol/pharmacology , DNA Damage , Sunscreening Agents/pharmacology , Ultraviolet Rays/adverse effects , 8-Hydroxy-2'-Deoxyguanosine , Deoxyguanosine/analogs & derivatives , Deoxyguanosine/metabolism , Drug Evaluation, Preclinical , Guanosine/analogs & derivatives , Guanosine/metabolism , Humans , Nitro Compounds/metabolism , Pyrimidine Dimers/metabolism , Reactive Nitrogen Species/metabolism , Reactive Oxygen Species/metabolism , Skin/drug effects , Skin/metabolism , Skin/radiation effects
10.
J Plast Reconstr Aesthet Surg ; 65(2): 195-200, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21992937

ABSTRACT

The achievement of patency of the microvascular anastomosis in free flap surgery is dependent on a number of factors, central to which is atraumatic handling of the vessel lumen, and intimal apposition. Initial laboratory studies demonstrating the superiority of the non-penetrating vascular closure staple (VCS - Anastoclip ®) were followed by our report in 1999 on a series of free flaps. There is still a paucity of data in the literature on the use of non-penetrating devices for microvascular anastomosis, and our review gives evidence to support the routine use of the VCS in microsurgical free flap surgery. We now report on its successful use over a thirteen year period in 819 free flap reconstructions. Our data indicates the VCS device to be as effective as sutured anastomoses in free tissue transfer surgery. There is also statistically significant data (Barnard's Exact Test) to demonstrate a higher vascular patency rate of the VCS device over sutured anastomoses when sub group analysis is performed. 'Take-back' revision rates were lower amongst flaps that employed VCS use. For arterial anastomoses, this equated to 3/654(0.05%) vs 4/170(2.4%) with hand-sewn anastomoses (p = 0.02). Similarly, for venous anastomoses the 'take-back' revision rate was 7/661(1.1%) vs 8/165(4.8%) with hand-sewn anastomoses (p = 0.003). Furthermore, the major advantage of the VCS is reduction in anastomosis time, from approximately 25 min per anastomosis for sutures to between five and 10 min for staples.


Subject(s)
Free Tissue Flaps/blood supply , Microvessels/surgery , Plastic Surgery Procedures/methods , Suture Techniques/instrumentation , Anastomosis, Surgical/instrumentation , Equipment Design , Female , Follow-Up Studies , Humans , Male , Retrospective Studies , Time Factors
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