RESUMO
Paternal influences on reproduction are significant causing about half of the infertile couples to turn to assisted reproductive techniques. Due to the increasing proportion of infertile couples adopting to conceive by in vitro fertilisation (IVF), predicting outcomes is of ever increasing importance. Since pregnancy rates following IVF are still quite low, prognostic information is very helpful in clinical decisions. Although significant research has been done on the maternal influence, male factor infertility is relatively understudied. To date, potential predictors include: method of fertilisation, age, reactive oxygen species, sperm quality parameters and DNA fragmentation. Predictors under investigation which show promising signs, even though there is no clear cut consensus on the predictive value to date include: folate and homocysteine, anti müllerian hormone measurement, environmental factors, body mass index, smoking, male age, stress, some subsets of antisperm antibodies and epigenetic features.
Assuntos
Infertilidade Masculina/terapia , Taxa de Gravidez , Técnicas de Reprodução Assistida , Espermatozoides/metabolismo , Hormônio Antimülleriano/sangue , Biomarcadores/sangue , Fragmentação do DNA , Feminino , Ácido Fólico/sangue , Homocisteína/sangue , Humanos , Infertilidade Masculina/sangue , Masculino , Gravidez , Prognóstico , Espécies Reativas de Oxigênio/metabolismo , Resultado do TratamentoRESUMO
The gut microbiome produces a range of short chain fatty acids (SCFA) crucially linked with diet and nutrition, metabolism, gastrointestinal health and homeostasis. SCFA are primarily measured using gas or liquid chromatography-mass spectrometry (LC/MS) after undergoing chemical derivatization. Here we assess the merits of a derivatization protocol using aniline and two aniline analogues (3-phenoxyaniline and 4-(benzyloxy)aniline) for the targeted LC-MS/MS quantification of nine SCFA (acetic, propionic, butyric, valeric, caproic acid, isobutyric, isovaleric, 2-methylbutyric, and 2-ethylbutyric acid). Evaluation of product ion spectra and optimization of MS detection conditions, provided superior detection sensitivity for 3-phenoxyaniline and 4-(benzyloxy)aniline compared to aniline. We developed a facile SCFA derivatization method using 3-phenoxyaniline under mild reaction conditions which allows for the simultaneous quantification of these SCFA in human stool samples in under eleven minutes using multiple reaction monitoring LC-MS/MS. The method was successfully validated and demonstrates intra- and inter-day accuracy (88.5-103% and 86.0-109%) and precision (CV of 0.55-7.00% and 0.33-9.55%) with recoveries (80.1-87.2% for LLOQ, 88.5-93.0% for ULOQ) and carry-over of (2.68-17.9%). Selectivity, stability and matrix effects were also assessed and satisfied validation criteria. Method applicability was demonstrated by analysing SCFA profiles in DNA-stabilized human stool samples from newly diagnosed colorectal cancer patients prior to surgery. The development of this improved method and its compatibility to measure SCFAs from DNA-stabilized stool will facilitate studies investigating the gut microbiome in health and disease.
Assuntos
Ácidos Graxos Voláteis , Espectrometria de Massas em Tandem , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Ácidos Graxos Voláteis/análise , Fezes/química , Ácido Acético , Compostos de Anilina/análise , Ácidos Graxos/análiseRESUMO
INTRODUCTION: Metastatic melanoma in the popliteal fossa is extremely rare with less than 5% of metastatic deposits from melanomas in the leg and foot draining into the popliteal region, while the majority drain to the inguinal region. If popliteal spread is clinically overlooked, it may lead to recurrence. Together with the accompanying literature review, this case report emphasises the need for thorough clinical and radiological assessment in the management of malignant melanomas of the lower extremity. PRESENTATION OF CASE: A 66-year-old gentleman presented with metastatic melanoma to the right popliteal fossa three years after the diagnosis of a primary lesion in the right mid-calf with ipsilateral inguinal lymph node metastasis for which he underwent a right wide local excision and complete groin lymph node dissection. DISCUSSION: Studies show that a lesion anywhere below the knee can metastasize to the popliteal fossa. The groin can be the primary or secondary lymphatic drainage site in conjunction with the popliteal fossa. Concurrent popliteal and inguinal drainage may either reflect two separate lymphatic channels with popliteal nodes being the primary drainage site, or a single channel which drains to the popliteal basin as an interval node. Hence, popliteal lymph nodes should be carefully assessed in distal lower extremity lesions including melanomas. Modalities to delineate lymphatic flow and identify micrometastatic deposits should be used and when metastatic popliteal disease is identified, radical popliteal dissection is advised. CONCLUSION: Proper clinical assessment, good surgical technique, a high index of suspicion, and active surveillance are all essential to ensure early detection of metastasis to the popliteal region.