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1.
Life Sci Alliance ; 7(5)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38458648

RESUMO

Plexiform neurofibromas (PNFs) are nerve tumors caused by loss of NF1 and dysregulation of RAS-MAPK signaling in Schwann cells. Most PNFs shrink in response to MEK inhibition, but targets with increased and durable effects are needed. We identified the anaphylatoxin C5a as increased in PNFs and expressed largely by PNF m acrophages. We defined pharmacokinetic and immunomodulatory properties of a C5aR1/2 antagonist and tested if peptide antagonists augment the effects of MEK inhibition. MEK inhibition recruited C5AR1 to the macrophage surface; short-term inhibition of C5aR elevated macrophage apoptosis and Schwann cell death, without affecting MEK-induced tumor shrinkage. PNF macrophages lacking C5aR1 increased the engulfment of dying Schwann cells, allowing their visualization. Halting combination therapy resulted in altered T-cell distribution, elevated Iba1+ and CD169+ immunoreactivity, and profoundly altered cytokine expression, but not sustained trumor shrinkage. Thus, C5aRA inhibition independently induces macrophage cell death and causes sustained and durable effects on the PNF microenvironment.


Assuntos
Citofagocitose , Neurofibroma Plexiforme , Humanos , Macrófagos/patologia , Quinases de Proteína Quinase Ativadas por Mitógeno , Neurofibroma Plexiforme/patologia , Transdução de Sinais , Microambiente Tumoral
2.
Int J STD AIDS ; 35(2): 103-111, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37933455

RESUMO

BACKGROUND: Selection of an antiretroviral regimen for people living with HIV (PLWH) involves various clinical considerations, such as comorbidities, archived drug resistance mutations, concomitant medications, and potential drug interactions and side effects. Alterations in the surface area and pH of the gastrointestinal tract following bariatric surgery may alter absorption, antiretroviral pharmacokinetics and viral suppression. Data on the efficacy of antiretroviral (ARV) therapy in PLWH who have undergone bariatric surgery are limited or lacking for new antiretrovirals, such as dolutegravir and bictegravir. METHODS: This case series reports virologic outcomes and side effects in eight cases of PLWH receiving ARV therapy who underwent bariatric surgery. A systematic literature review was performed to review the available literature on the efficacy and safety of antiretroviral regimens in PLWH who have undergone bariatric surgery. RESULTS: Virologic suppression was not impacted for obese PLWH who underwent bariatric surgery following failure of life-style modifications and pharmacological therapy. CONCLUSIONS: There were no deleterious effects on HIV progression for PLWH that underwent bariatric surgery. More prospective research is required to validate the effects of bariatric surgery on immunologic and virologic function outcomes. Close involvement of HIV and surgical specialists is recommended to manage ARV therapy in patients undergoing bariatric surgery.


Assuntos
Fármacos Anti-HIV , Cirurgia Bariátrica , Infecções por HIV , HIV-1 , Humanos , Fármacos Anti-HIV/uso terapêutico , Cirurgia Bariátrica/efeitos adversos , Infecções por HIV/tratamento farmacológico , Soropositividade para HIV/tratamento farmacológico , HIV-1/fisiologia , Estudos Prospectivos
3.
Br J Anaesth ; 131(2): 328-337, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37271721

RESUMO

BACKGROUND: Animal studies have shown that isoflurane and propofol have differential effects on Alzheimer's disease (AD) pathology and memory, although it is unclear whether this occurs in humans. METHODS: This was a nested randomised controlled trial within a prospective cohort study; patients age ≥60 yr undergoing noncardiac/non-neurological surgery were randomised to isoflurane or propofol for anaesthetic maintenance. Cerebrospinal fluid (CSF) was collected via lumbar puncture before, 24 h, and 6 weeks after surgery. Cognitive testing was performed before and 6 weeks after surgery. Nonparametric methods and linear regression were used to evaluate CSF biomarkers and cognitive function, respectively. RESULTS: There were 107 subjects (54 randomised to isoflurane and 53 to propofol) who completed the 6-week follow-up and were included in the analysis. There was no significant effect of anaesthetic treatment group, time, or group-by-time interaction for CSF amyloid-beta (Aß), tau, or phospho-tau181p levels, or on the tau/Aß or p-tau181p/Aß ratios (all P>0.05 after Bonferroni correction). In multivariable-adjusted intention-to-treat analyses, there were no significant differences between the isoflurane and propofol groups in 6-week postoperative change in overall cognition (mean difference [95% confidence interval]: 0.01 [-0.12 to 0.13]; P=0.89) or individual cognitive domains (P>0.05 for each). Results remained consistent across as-treated and per-protocol analyses. CONCLUSIONS: Intraoperative anaesthetic maintenance with isoflurane vs propofol had no significant effect on postoperative cognition or CSF Alzheimer's disease-related biomarkers within 6 weeks after noncardiac, non-neurological surgery in older adults. CLINICAL TRIAL REGISTRATION: NCT01993836.


Assuntos
Doença de Alzheimer , Anestésicos , Isoflurano , Propofol , Humanos , Idoso , Propofol/farmacologia , Isoflurano/farmacologia , Estudos Prospectivos , Proteínas tau/líquido cefalorraquidiano , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Fragmentos de Peptídeos/líquido cefalorraquidiano
4.
Genetics ; 224(1)2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-36919976

RESUMO

The genes that encode ribosomal RNAs are present in several hundred copies in most eukaryotes. These vast arrays of repetitive ribosomal DNA (rDNA) have been implicated not just in ribosome biogenesis, but also aging, cancer, genome stability, and global gene expression. rDNA copy number is highly variable among and within species; this variability is thought to associate with traits relevant to human health and disease. Here we investigate the phenotypic consequences of multicellular life at the lower bounds of rDNA copy number. We use the model Caenorhabditis elegans, which has previously been found to complete embryogenesis using only maternally provided ribosomes. We find that individuals with rDNA copy number reduced to ∼5% of wild type are capable of further development with variable penetrance. Such individuals are sterile and exhibit severe morphological defects, particularly in post-embryonically dividing tissues such as germline and vulva. Developmental completion and fertility are supported by an rDNA copy number ∼10% of wild type, with substantially delayed development. Worms with rDNA copy number reduced to ∼33% of wild type display a subtle developmental timing defect that was absent in worms with higher copy numbers. Our results support the hypothesis that rDNA requirements vary across tissues and indicate that the minimum rDNA copy number for fertile adulthood is substantially less than the lowest naturally observed total copy number. The phenotype of individuals with severely reduced rDNA copy number is highly variable in penetrance and presentation, highlighting the need for continued investigation into the biological consequences of rDNA copy number variation.


Assuntos
Caenorhabditis elegans , Variações do Número de Cópias de DNA , Animais , Feminino , Humanos , Adulto , DNA Ribossômico/genética , Caenorhabditis elegans/genética , Ribossomos , Fenótipo
5.
Oncogene ; 42(13): 1038-1047, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36759572

RESUMO

Neurofibromatosis type 1 (NF1) patients are predisposed to develop plexiform neurofibromas (PNFs). Three endoplasmic reticulum (ER) stress response pathways restore cellular homeostasis. The unfolded protein response (UPR) sensors contribute to tumor initiation in many cancers. We found that all three UPR pathways were activated in mouse and human PNFs, with protein kinase RNA [PKR]-like ER kinase (PERK) the most highly expressed. We tested if neurofibroma cells adapt to ER stress, leading to their growth. Pharmacological or genetic inhibition of PERK reduced mouse neurofibroma-sphere number, and genetic inhibition in PERK in Schwann cell precursors (SCPs) decreased tumor-like lesion numbers in a cell transplantation model. Further, in a PNF mouse model, deletion of PERK in Schwann cells (SCs) and SCPs reduced tumor size, number, and increased survival. Mechanistically, loss of Nf1 activated PERK-eIF2α-ATF4 signaling and increased ATF4 downstream target gene p21 translocation from nucleus to cytoplasm. This nucleus-cytoplasm translocation was mediated by exportin-1. Runx transcriptionally activated ribosome gene expression and increased protein synthesis to allow SCs to adapt to ER stress and tumor formation. We propose that targeting proteostasis might provide cytotoxic and/or potentially durable novel therapy for PNFs.


Assuntos
Neurofibroma Plexiforme , Neurofibroma , Neurofibromatose 1 , Animais , Humanos , Camundongos , Subunidade alfa 2 de Fator de Ligação ao Core/genética , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo , Estresse do Retículo Endoplasmático/genética , Resposta a Proteínas não Dobradas/genética
6.
Br J Anaesth ; 127(6): 917-928, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34535274

RESUMO

BACKGROUND: Cognitive dysfunction after surgery is a major issue in older adults. Here, we determined the effect of APOE4 on perioperative neurocognitive function in older patients. METHODS: We enrolled 140 English-speaking patients ≥60 yr old scheduled for noncardiac surgery under general anaesthesia in an observational cohort study, of whom 52 underwent neuroimaging. We measured cognition; Aß, tau, p-tau levels in CSF; and resting-state intrinsic functional connectivity in six Alzheimer's disease-risk regions before and 6 weeks after surgery. RESULTS: There were no significant APOE4-related differences in cognition or CSF biomarkers, except APOE4 carriers had lower CSF Aß levels than non-carriers (preoperative median CSF Aß [median absolute deviation], APOE4 305 pg ml-1 [65] vs 378 pg ml-1 [38], respectively; P=0.001). Controlling for age, APOE4 carriers had significantly greater preoperative functional connectivity than non-carriers between several brain regions implicated in Alzheimer's disease, including between the left posterior cingulate cortex and left angular gyrus (ß [95% confidence interval, CI], 0.218 [0.137-0.230]; PFWE=0.016). APOE4 carriers, but not non-carriers, experienced significant connectivity decreases from before to 6 weeks after surgery between several brain regions including between the left posterior cingulate cortex and left angular gyrus (ß [95% CI], -0.196 [-0.256 to -0.136]; PFWE=0.001). Most preoperative and postoperative functional connectivity differences did not change after controlling for preoperative CSF Aß levels. CONCLUSIONS: Postoperative change trajectories for cognition and CSF Aß, tau or p-tau levels did not differ between community dwelling older APOE4 carriers and non-carriers. APOE4 carriers showed greater preoperative functional connectivity and greater postoperative decreases in functional connectivity in key Alzheimer's disease-risk regions, which occur via Aß-independent mechanisms.


Assuntos
Apolipoproteína E4/sangue , Disfunção Cognitiva/sangue , Disfunção Cognitiva/diagnóstico por imagem , Neuroimagem Funcional/métodos , Avaliação Geriátrica/métodos , Assistência Perioperatória/métodos , Idoso , Encéfalo/diagnóstico por imagem , Estudos de Coortes , Feminino , Humanos , Masculino , Estudos Prospectivos
7.
Cureus ; 13(3): e13783, 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33842158

RESUMO

Pheochromocytomas (PCC) are rare neuroendocrine tumors of the adrenal medulla that arise from chromaffin cells. These cells are neural crest derivatives and are innervated by the splanchnic nerve of the sympathetic nervous system which releases acetylcholine that in turn binds to nicotinic acetylcholine receptors of the adrenal medulla causing the release of catecholamines. The dopamine, norepinephrine, and epinephrine released from these tumors are responsible for the episodic hyperadrenergic symptoms seen in these cases such as hypertension, palpitations, and headaches. This case report discusses the incidental finding of a unilateral PCC in a 58-year-old woman who initially presented to our emergency department complaining of intermittent chest pain and headaches for two days.

8.
J Alzheimers Dis ; 80(3): 1281-1297, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33682719

RESUMO

BACKGROUND: Postoperative cognitive dysfunction (POCD), a syndrome of cognitive deficits occurring 1-12 months after surgery primarily in older patients, is associated with poor postoperative outcomes. POCD is hypothesized to result from neuroinflammation; however, the pathways involved remain unclear. Unbiased proteomic analyses have been used to identify neuroinflammatory pathways in multiple neurologic diseases and syndromes but have not yet been applied to POCD. OBJECTIVE: To utilize unbiased mass spectrometry-based proteomics to identify potential neuroinflammatory pathways underlying POCD. METHODS: Unbiased LC-MS/MS proteomics was performed on immunodepleted cerebrospinal fluid (CSF) samples obtained before, 24 hours after, and 6 weeks after major non-cardiac surgery in older adults who did (n = 8) or did not develop POCD (n = 6). Linear mixed models were used to select peptides and proteins with intensity differences for pathway analysis. RESULTS: Mass spectrometry quantified 8,258 peptides from 1,222 proteins in > 50%of patient samples at all three time points. Twelve peptides from 11 proteins showed differences in expression over time between patients with versus withoutPOCD (q < 0.05), including proteins previously implicated in neurodegenerative disease pathophysiology. Additionally, 283 peptides from 182 proteins were identified with trend-level differences (q < 0.25) in expression over time between these groups. Among these, pathway analysis revealed that 50 were from 17 proteins mapping to complement and coagulation pathways (q = 2.44*10-13). CONCLUSION: These data demonstrate the feasibility of performing unbiased mass spectrometry on perioperative CSF samples to identify pathways associated with POCD. Additionally, they provide hypothesis-generating evidence for CSF complement and coagulation pathway changes in patients with POCD.


Assuntos
Biomarcadores/líquido cefalorraquidiano , Complicações Cognitivas Pós-Operatórias/líquido cefalorraquidiano , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Masculino , Proteoma/análise , Espectrometria de Massas em Tandem
9.
Sci Rep ; 11(1): 449, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33432083

RESUMO

The ribosomal RNA genes (rDNA) are tandemly arrayed in most eukaryotes and exhibit vast copy number variation. There is growing interest in integrating this variation into genotype-phenotype associations. Here, we explored a possible association of rDNA copy number variation with autism spectrum disorder and found no difference between probands and unaffected siblings. Because short-read sequencing estimates of rDNA copy number are error prone, we sought to validate our 45S estimates. Previous studies reported tightly correlated, concerted copy number variation between the 45S and 5S arrays, which should enable the validation of 45S copy number estimates with pulsed-field gel-verified 5S copy numbers. Here, we show that the previously reported strong concerted copy number variation may be an artifact of variable data quality in the earlier published 1000 Genomes Project sequences. We failed to detect a meaningful correlation between 45S and 5S copy numbers in thousands of samples from the high-coverage Simons Simplex Collection dataset as well as in the recent high-coverage 1000 Genomes Project sequences. Our findings illustrate the challenge of genotyping repetitive DNA regions accurately and call into question the accuracy of recently published studies of rDNA copy number variation in cancer that relied on diverse publicly available resources for sequence data.


Assuntos
Variações do Número de Cópias de DNA/genética , DNA/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , RNA Ribossômico 5S/genética , RNA Ribossômico/genética , Transtorno do Espectro Autista/genética , Confiabilidade dos Dados , Conjuntos de Dados como Assunto , Técnicas de Genotipagem , Projeto Genoma Humano , Humanos , Neoplasias/genética , Sequências Repetitivas de Ácido Nucleico/genética , Análise de Sequência de DNA
10.
Oncogene ; 40(5): 951-963, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33293695

RESUMO

MicroRNAs (miRs) are small non-coding RNAs that can have large impacts on oncogenic pathways. Possible functions of dysregulated miRs have not been studied in neurofibromatosis type 1 (NF1) plexiform neurofibromas (PNFs). In PNFs, Schwann cells (SCs) have biallelic NF1 mutations necessary for tumorigenesis. We analyzed a miR microarray comparing with normal and PNF SCs and identified differences in miR expression, and we validated in mouse PNFs versus normal mouse SCs by qRT-PCR. Among these, miR-155 was a top overexpressed miR, and its expression was regulated by RAS/MAPK signaling. Overexpression of miR-155 increased mature Nf1-/- mouse SC proliferation. In SC precursors, which model tumor-initiating cells, pharmacological and genetic inhibition of miR-155 decreased PNF-derived sphere numbers in vitro, and we identified Maf as a miR-155 target. In vivo, global deletion of miR-155 significantly decreased tumor number and volume, increasing mouse survival. Fluorescent nanoparticles entered PNFs, suggesting that an anti-miR might have therapeutic potential. However, treatment of established PNFs using anti-miR-155 peptide nucleic acid-loaded nanoparticles marginally decreased tumor numbers and did not reduce tumor growth. These results suggest that miR-155 plays a functional role in PNF growth and/or SC proliferation, and that targeting neurofibroma miRs is feasible, and might provide novel therapeutic opportunities.


Assuntos
MicroRNAs/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Neurofibroma/genética , Neurofibromina 1/genética , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Humanos , Camundongos , Camundongos Knockout , Neurofibroma/patologia , Células de Schwann/metabolismo , Células de Schwann/patologia
11.
Sci Adv ; 5(4): eaau8389, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31032403

RESUMO

Patients with neurofibromatosis type 1 (NF1) are predisposed to develop neurofibromas, but the underlying molecular mechanisms of neurofibromagenesis are not fully understood. We showed dual genetic deletion of Runx1 and Runx3 in Schwann cells (SCs) and SC precursors delayed neurofibromagenesis and prolonged mouse survival. We identified peripheral myelin protein 22 (Pmp22/Gas3) related to neurofibroma initiation. Knockdown of Pmp22 with short hairpin RNAs increased Runx1fl/fl;Runx3fl/fl;Nf1fl/fl;DhhCre tumor-derived sphere numbers and enabled significantly more neurofibroma-like microlesions on transplantation. Conversely, overexpression of Pmp22 in mouse neurofibroma SCs decreased cell proliferation. Mechanistically, RUNX1/3 regulated alternative promoter usage and induced levels of protein expression of Pmp22 to control SC growth. Last, pharmacological inhibition of RUNX/core-binding factor ß (CBFB) activity significantly reduced neurofibroma volume in vivo. Thus, we identified a signaling pathway involving RUNX1/3 suppression of Pmp22 in neurofibroma initiation and/or maintenance. Targeting disruption of RUNX/CBFB interaction might provide a novel therapy for patients with neurofibroma.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteínas da Mielina/metabolismo , Neurofibroma/metabolismo , Alelos , Animais , Sequência de Bases , Proliferação de Células , Sobrevivência Celular , Subunidade beta de Fator de Ligação ao Core/metabolismo , Feminino , Deleção de Genes , Humanos , Masculino , Camundongos , Camundongos Nus , Regiões Promotoras Genéticas , RNA Interferente Pequeno/metabolismo , Células de Schwann/metabolismo , Transdução de Sinais , Transcriptoma
12.
J Law Med Ethics ; 46(2): 351-366, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30146985

RESUMO

The devastating impact of the national opioid epidemic has given rise to hundreds of lawsuits. This article details the extremely broad range of legal claims, compares the opioid cases to other public health litigation efforts, including tobacco, and describes the special mechanism - a multidistrict litigation - through which more than 700 opioid-related cases have been consolidated thus far, with settlement almost certain to follow.


Assuntos
Indústria Farmacêutica/legislação & jurisprudência , Joint Commission on Accreditation of Healthcare Organizations/legislação & jurisprudência , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Farmácias/legislação & jurisprudência , Médicos/legislação & jurisprudência , Analgésicos Opioides/efeitos adversos , Humanos , Estados Unidos/epidemiologia
13.
Oncotarget ; 7(17): 23498-511, 2016 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-27015557

RESUMO

Among breast cancer types, triple-negative breast cancer (TNBC) has the fewest treatment options and the lowest 5-year survival rate. Androgen receptor (AR) inhibition has displayed efficacy against breast cancer preclinically and is currently being examined clinically in AR positive TNBC patients. Androgen deprivation has been shown to induce immunogenic modulation; the alteration of tumor cell phenotype resulting in increased sensitivity to immune-mediated killing. We evaluated the ability of AR inhibition to reduce the growth and improve the immune-mediated killing of breast cancer cells with differing expression of the estrogen receptor and AR. While AR expression was required for the growth inhibitory effects of enzalutamide on breast cancer cells, both enzalutamide and abiraterone improved the sensitivity of breast cancer cells to immune-mediated lysis independent of detectable AR expression. This increase in sensitivity was linked to an increase in cell surface tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor expression as well as a significant reduction in the expression of osteoprotegerin (OPG). The reduction in OPG was further examined and found to be critical for the increase in sensitivity of AR- TNBC cells to immune-mediated killing. The data presented herein further support the use of AR inhibition therapy in the AR+ TNBC setting. These data, however, also support the consideration of AR inhibition therapy for the treatment of AR- TNBC, especially in combination with cancer immunotherapy, providing a potential novel therapeutic option for select patients.


Assuntos
Antagonistas de Androgênios/farmacologia , Imunoterapia , Osteoprotegerina/metabolismo , Feniltioidantoína/análogos & derivados , Receptores Androgênicos/química , Linfócitos T Citotóxicos/imunologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Apoptose/efeitos dos fármacos , Benzamidas , Biomarcadores Tumorais/metabolismo , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Imunomodulação , Nitrilas , Feniltioidantoína/farmacologia , Receptores Androgênicos/metabolismo , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Células Tumorais Cultivadas
15.
Artigo em Inglês | MEDLINE | ID: mdl-22521213

RESUMO

An LC-MS/MS method for the quantitation of urinary metabolites of eight JWH-type synthetic cannabinoids (SCs) has been developed and validated. Urine samples are subjected to deconjugation using ß-glucuronidase, followed by a solvent extraction procedure. Compounds are separated on a reverse-phase HPLC column within a 14 min cycle. Low assay limits are required in order to demonstrate prior exposure to SCs. Matrix effects were studied and proved to be significant for selected analytes, and were challenging to circumvent as isotope-labeled internal standards are not available. An elimination profile from a naïve user following a single smoke of "Kronic" was constructed, showing urinary excretion over 2-3 days with peak concentrations of different metabolites 3-16.5 h after smoking. This method has been developed to process several hundred samples within a high-throughput drugs of abuse laboratory, with growing evidence that the use of synthetic cannabinoid blends is common within the Australian workforce.


Assuntos
Canabinoides/urina , Cromatografia de Fase Reversa/métodos , Indóis/urina , Naftalenos/urina , Espectrometria de Massas em Tandem/métodos , Acetatos , Acetonitrilas , Austrália , Cromatografia Líquida de Alta Pressão/métodos , Drogas Desenhadas , Humanos , Drogas Ilícitas , Indóis/metabolismo , Modelos Lineares , Metanol , Naftalenos/metabolismo , Reprodutibilidade dos Testes
16.
Forensic Sci Int ; 136(1-3): 58-72, 2003 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-12969621

RESUMO

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.


Assuntos
Cromossomos Humanos Y/genética , Medicina Legal/métodos , Estupro , Sêmen , Espermatozoides , Sequências de Repetição em Tandem , Coito , Impressões Digitais de DNA , Feminino , Humanos , Masculino , Sensibilidade e Especificidade , Fatores de Tempo , Esfregaço Vaginal
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