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1.
Occup Med (Lond) ; 72(4): 260-263, 2022 05 23.
Article in English | MEDLINE | ID: mdl-35233606

ABSTRACT

BACKGROUND: There has been increasing evidence that physicians in gynaecology are not routinely enquiring about work during consultations. AIMS: To explore the effect gynaecological conditions can have on work functioning, the importance of work outcomes among patients and whether work considerations are discussed during clinical consultations. METHODS: A cross-sectional survey was administered to employed patients attending a gynaecological clinic at Guy's Hospital. The survey assessed four areas: demographics, gynaecological condition (including self-assessed severity), work status and perceived impact of the condition on work functioning and job satisfaction. Simple descriptive analysis and statistical techniques were used to interpret the data. RESULTS: One hundred and six participants participated (mean age: 37.49 ±â€…9.09). About 95% found it important to be able to work whilst receiving treatment and 82% of patients had reported at least a slight impact on their working ability due to their condition. Of the 31 patients for whom it was their first appointment, 77% said it would be useful to discuss the possible impacts their gynaecological condition could have on their work. About 66% (19/29) of the participants attending a follow-up appointment reported that their doctor had not discussed their work with them. CONCLUSIONS: The symptoms of gynaecological conditions can impact patients' ability to work. There is a lack of useful discussion from doctors about the perceived impact gynaecological conditions can have on a patient's ability to work, despite patients finding it important to be able to remain or return to work.


Subject(s)
Gynecology , Physicians , Adult , Cross-Sectional Studies , Humans , Job Satisfaction , Middle Aged , Surveys and Questionnaires
2.
J Magn Reson ; 333: 107080, 2021 12.
Article in English | MEDLINE | ID: mdl-34689098

ABSTRACT

OBJECT: This paper presents a new method using tangent vector-based l12-regularization for compressed sensing MR image reconstruction. MATERIALS AND METHODS: The proposed method with l12-regularization is tested on four datasets: (i) 1-D sparse signal (ii) numerical cardiac phantom, (iii & iv) two sets of in-vivo cardiac MRI datasets acquired using 30 receiver coil elements with Cartesian and radial trajectories on 3T scanner. The results are compared with standard CS reconstruction, which utilizes l1-regularization. The experiments were also conducted for two different types of samplings: (i) cartesian sub-sampling and (ii) 2D random Gaussian sub-sampling. RESULTS: The quality of the reconstructed images is validated through Root Mean Square Error (RMSE) and Peak Signal-to-Noise Ratio (PSNR). The results show that the proposed method outperforms the standard CS reconstructions in our experiments with an improvement of 54.8% in RMSE and 14.3% in terms of PSNR. Moreover, the Gaussian random sub-sampling-based image reconstruction results are better than the Cartesian sub-sampling-based reconstruction results. CONCLUSION: The results show that the proposed method yields a good sparse signal approximation and superior convergence behavior, which implies a promising technique for the reconstruction of cardiac MR images as compared to the conventional CS algorithm.


Subject(s)
Algorithms , Magnetic Resonance Imaging , Image Processing, Computer-Assisted , Normal Distribution , Phantoms, Imaging , Signal-To-Noise Ratio
3.
Radiat Prot Dosimetry ; 154(3): 364-74, 2013.
Article in English | MEDLINE | ID: mdl-23019598

ABSTRACT

Neutron spectrometry and subsequent dosimetry measurements were undertaken at the McMaster Nuclear Reactor (MNR) and AECL Chalk River National Research Universal (NRU) Reactor. The instruments used were a Bonner sphere spectrometer (BSS), a cylindrical nested neutron spectrometer (NNS) and a commercially available rotational proton recoil spectrometer. The purposes of these measurements were to: (1) compare the results obtained by three different neutron measuring instruments and (2) quantify neutron fields of interest. The results showed vastly different neutron spectral shapes for the two different reactors. This is not surprising, considering the type of the reactors and the locations where the measurements were performed. MNR is a heavily shielded light water moderated reactor, while NRU is a heavy water moderated reactor. The measurements at MNR were taken at the base of the reactor pool, where a large amount of water and concrete shielding is present, while measurements at NRU were taken at the top of the reactor (TOR) plate, where there is only heavy water and steel between the reactor core and the measuring instrument. As a result, a large component of the thermal neutron fluence was measured at MNR, while a negligible amount of thermal neutrons was measured at NRU. The neutron ambient dose rates at NRU TOR were measured to be between 0.03 and 0.06 mSv h⁻¹, while at MNR, these values were between 0.07 and 2.8 mSv h⁻¹ inside the beam port and <0.2 mSv h⁻¹ between two operating beam ports. The conservative uncertainty of these values is 15 %. The conservative uncertainty of the measured integral neutron fluence is 5 %. It was also found that BSS over-responded slightly due to a non-calibrated response matrix.


Subject(s)
Neutrons , Nuclear Reactors/instrumentation , Occupational Exposure/analysis , Radiation Monitoring/instrumentation , Radiation Protection/instrumentation , Spectrum Analysis/instrumentation , Canada , Equipment Design , Equipment Failure Analysis , Reproducibility of Results , Sensitivity and Specificity
4.
Hum Reprod ; 15(10): 2154-9, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11006191

ABSTRACT

With the advancement of medical science, most cancers in children are now treatable, the cure rate being almost 85%. In boys, one side effect of treatment (chemotherapy and radiotherapy) is destruction of the sperm precursor cells in the testis, resulting in the failure of sperm formation after puberty, and consequent infertility. At the time of anti-cancer treatment, future fertility of the boy patient is at the very bottom of the relative quality of life (RQL) parameters list; however, in adults infertility is an important issue following cure from cancer. In this article we have first reviewed the existing situation with regard to the state of the art of fertility preservation in young boys with cancer, and have then raised clinical and ethical issues and suggested a way forward. The review concludes with the emphasis that certain important issues still need to be resolved and, until these are, then the different techniques available should be confined to approved, ethical clinical trials where efficacy and safety can be fully evaluated.


Subject(s)
Antineoplastic Agents/adverse effects , Cell Transplantation/methods , Cryopreservation/methods , Infertility, Male/chemically induced , Infertility, Male/prevention & control , Testis/transplantation , Adolescent , Adult , Cell Transplantation/legislation & jurisprudence , Child , Ethics, Medical , Forecasting , Humans , Infertility, Male/therapy , Male , Neoplasms/epidemiology , Neoplasms/therapy , Puberty , Spermatogonia/drug effects , Spermatogonia/radiation effects , Stem Cell Transplantation , Testis/cytology
5.
Hum Reprod ; 15(6): 1278-83, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10831555

ABSTRACT

The objective of this study was to examine different clinical scenarios of in-vitro conception, viz. fertilization with conventional IVF, IVF with high insemination concentration (HIC) and intracytoplasmic sperm injection (ICSI), and assess on a sibling oocyte comparison the hypothesis that ICSI should be performed in all cases requiring in-vitro conception. ICSI with husband's spermatozoa had a higher incidence of fertilization as compared with IVF or IVF with HIC with donor spermatozoa (if previous failure of fertilization had occurred) for unexplained infertility. Similarly, ICSI with husband's spermatozoa had as high an incidence of fertilization as IVF with donor spermatozoa for patients with severe oligozoospermia, asthenozoospermia and/or teratozoospermia, even when the spermatozoa were not selected for their morphology. Two studies were performed to assess ICSI in potential oocyte-related failure of IVF, viz. when fertilization occurred in >50% of oocytes for one group of patients, and in <50% of oocytes in a second group. In both of these studies a significant proportion of the oocytes that failed to fertilize with conventional IVF eventually fertilized after ICSI. The overall conclusion was that ICSI as a first option offers a higher incidence of fertilization, maximizes the number of embryos and minimizes the risk of complete failure of fertilization for all cases requiring in-vitro conception. However, among other concerns, current knowledge of ICSI as an outcome procedure does not provide the confidence to use this process in all cases of IVF for the time being.


Subject(s)
Fertilization in Vitro/methods , Sperm Injections, Intracytoplasmic , Female , Fertilization , Humans , Insemination, Artificial, Heterologous , Insemination, Artificial, Homologous , Prospective Studies , Retreatment , Treatment Failure
6.
Mol Hum Reprod ; 5(8): 784-7, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10421808

ABSTRACT

Human elongated spermatids from azoospermic patients were inserted into mouse oocytes by intracytoplasmic sperm injection (ICSI). The injection resulted in survival rates of 46.5% (180 out of 387) and activation rates of 36.1% (65 out of 180). The rate of two pronuclear (2PN) formation was 35.4% (23 out of 65). Only 34.8% (eight out of 23) metaphase chromosome spreads from 2PN zygotes could be analysed; however, all were of normal karyotype. Cytogenetic analysis at the first metaphase revealed that human elongated spermatid chromosomes were able to undergo replication in a heterogeneous environment.


Subject(s)
Chromosomes/ultrastructure , Spermatids/ultrastructure , Animals , Chromosomes/genetics , Female , Fertilization in Vitro , Humans , Karyotyping , Male , Metaphase/genetics , Mice , Microinjections , Oocytes/ultrastructure
7.
Hum Reprod ; 14(6): 1528-33, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10357970

ABSTRACT

The clinical potential for fertilization was examined by using the human sperm-hamster oocyte assay system after microinjection of round (RS), elongating (ES) or elongated (EtedS) spermatids retrieved from obstructive and non-obstructive azoospermic patients. Freshly isolated, in-vitro cultured and cryopreserved spermatids were utilized. For each category of microinjected spermatids, we demonstrated that the more mature the injected spermatid, the higher the incidence of fertilization (for freshly isolated spermatids, P < 0.006 and P < 0.008, for in-vitro cultured spermatids, P < 0.007 and P < 0.007 and for cryopreserved spermatids, P < 0.006 and P < 0.007 for obstructive and non-obstructive azoospermic patients respectively). Short term in-vitro culture of the spermatogenic cells did not improve the incidence of fertilization. However, cryopreservation significantly decreased (P < 0.001) the incidence of fertilization when each corresponding spermatogenic cell stage was compared. The incidence of fertilization was not statistically different when corresponding stages of spermatogenic cells were compared from obstructive and non-obstructive patients.


Subject(s)
Cryopreservation , Fertilization in Vitro/methods , Microinjections , Oligospermia/physiopathology , Oocytes , Spermatids/physiology , Animals , Cells, Cultured , Cricetinae , Female , Humans , Male , Oligospermia/pathology
8.
Hum Reprod Update ; 4(3): 213-22, 1998.
Article in English | MEDLINE | ID: mdl-9741706

ABSTRACT

During 1995 and 1996 the first spermatid pregnancies were announced with both round spermatid (ROSI) and elongated spermatid (ELSI) injections. These publications were flanked by live births from ROSI in a number of animal species, with resulting offspring appearing normal, healthy and fertile. However, the live births in humans heralded a scientific and ethical debate on the clinical use of this technology; and in a number of countries nationwide moratoria prohibiting spermatid microinjection were enjoined. Concerns surrounded the biological condition of spermatids and clinical implications of utilizing an immature spermatozoon for conception. Nevertheless, case reports and a few scientific studies on human spermatid conception have been published in recent years, and further polemic on testicular histopathology and prognosis has ensued. This paper reviews the current arguments on the clinical use of ROSI and ELSI, and evaluates the biology of the main contributory components of a spermatozoon to the subsequent embryo, namely the genetic material, the microtubular organizing complex and the putative oocyte activating factor. We also consider the relevant testicular histopathology and likely outcome in the context of the current birth rate from ROSI and ICSI. We conclude by considering the way forward for infertile men who require this technology to become genetic fathers, and whether the time is now appropriate to consider clinical trials.


Subject(s)
Fertilization in Vitro/methods , Infertility, Male/therapy , Microinjections , Spermatids , Clinical Trials as Topic , Female , Humans , Male , Spermatids/ultrastructure , Treatment Outcome
9.
Hum Reprod ; 13(3): 634-8, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9572425

ABSTRACT

Testicular cell suspensions were prepared from obstructive and non-obstructive azoospermic men and were cultured in vitro for 96 h as (i) mixed cell populations and (ii) isolated homogeneous populations of primary spermatocytes, round spermatids and elongating spermatids. The cells lost their viability gradually during the first 24 h period. By 72 h almost 90% of the cells were non-viable. Isolated pure fractions showed better viability at each time interval (P < 0.0005). Throughout the culture period primary spermatocytes, elongating spermatids and other non-spermatogenic cells showed no change in their morphology, but almost 22% of round spermatids showed growth of flagella. Most of the round spermatids developed their flagella during the first 4-8 h period of culture. Isolated pure round spermatids showed better flagellar growth compared with mixed cell suspensions (P < 0.0005). The spermatogenic cells were successfully cryopreserved. However, when mixed spermatogenic cell suspensions were cryopreserved, more cells lost their viability compared with when isolated pure fractions were cryopreserved (P < 0.0005).


Subject(s)
Cryopreservation , Fertilization in Vitro , Spermatozoa/physiology , Cell Survival , Cells, Cultured , Humans , Infertility, Male/therapy , Male , Oligospermia/pathology , Sperm Tail/physiology , Spermatids/ultrastructure , Spermatozoa/pathology , Time Factors
10.
Hum Reprod ; 13(3): 639-45, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9572426

ABSTRACT

The success of spermatid microinjection has generated many concerns. In particular, there is a lack of appropriate methodology for the isolation of large homogeneous populations of spermatids, with minimum loss of viability, from the testicular tissue of azoospermic men. Here we have compared two different isolation methods -- velocity sedimentation under unit gravity (VSUG) combined with discontinuous Percoll centrifugation (DPC), and separation with fluorescent-activated cell sorter (FACS) using light in the visible range -- to determine the most suitable method for the isolation of spermatids. Total mixed cell count/gram of testicular parenchyma was significantly higher in obstructive azoospermic men compared with non-obstructive azoospermic men (P < 0.001). The results of the comparison showed that in obstructive azoospermic patients the difference in the yields of primary spermatocytes produced by the two techniques was not significant, but for round and elongating spermatids the FACS separation proved to be the better method (P < 0.001). Similarly, in non-obstructive azoospermic patients, FACS separation proved to be superior, giving increased yields of primary spermatocytes and round and elongating spermatids compared with VSUG combined with DPC method (P < 0.001). More than 99 % of the separated cells retained their viability after FACS separation. As large homogeneous populations of viable spermatids can be separated with FACS in a relatively short period of time, FACS separation is the most suitable method for the isolation of spermatids from testicular biopsy tissue.


Subject(s)
Cell Separation/methods , Oligospermia/pathology , Spermatids/pathology , Spermatozoa/pathology , Testis/pathology , Cell Survival , Deoxyribonuclease I , Flow Cytometry , Humans , Male , Trypsin
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