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1.
Horm Behav ; 156: 105444, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38344953

RESUMO

This study examined the effect of 6 weeks of supraphysiological nandrolone decanoate (ND) administration in adult mice (7 months) on cognitive function and neuroinflammation during aging. Male C57BL/6 mice were randomized into ND (10 mg·kg-1·wk-1) or control (CTL) groups. Half of the mice were tested at a young (Y) age (ND-Y and CTL-Y), 1 week following final ND administration, while the remaining mice were tested at 16 months (O) (ND-O and CTL-O). Learning and memory were better in young mice compared to older mice, regardless of treatment. ND-O displayed decreased anxiety as compared to all other groups. TNFα and IL1ß expression were higher in older mice, regardless of treatment. ND administration in young mice appeared to attenuate the neuroinflammatory response in aging mice as evidenced by decreased COX2, IL-4 and increased IL-10 expression in ND-O compared to CTL-O. BDNF AR and ER expression increased in ND-O compared to CTL-O. Results of the study indicated that supraphysiological ND administration had no negative effect on learning and memory but may attenuate anxiety in older mice. In addition, ND administration in young adult mice may attenuate the inflammatory response during aging, which may be related to elevations in both AR and ER expression.


Assuntos
Anabolizantes , Nandrolona , Masculino , Camundongos , Animais , Decanoato de Nandrolona , Nandrolona/farmacologia , Anabolizantes/farmacologia , Fatores de Crescimento Neural , Camundongos Endogâmicos C57BL
3.
Clin Transl Radiat Oncol ; 41: 100631, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37168253

RESUMO

Background: Surgery is the primary treatment for most meningiomas. However, primary fractionated radiotherapy (fRT) remains an option for patients with larger meningiomas in challenging anatomic locations or patients at prohibitively high surgical risk. Outcome prediction for these patients is uncertain and cannot be guided by histopathology without available tumor tissue from surgery. Therefore, we aimed to assess the clinical factors that contribute to treatment failure in a large cohort of meningiomas consecutively treated with fRT as primary therapy, with the goal of identifying predictors of response. Methods: Patients treated with primary fRT for intracranial meningiomas from 1998 to 2017 were reviewed. Those who received primary surgical resection, radiosurgery, previous fRT, or had <6 months of clinical follow-up were excluded. We applied logistic regression and Cox regression modeling to ascertain key predictors of treatment failure, progression-free survival (PFS), and adverse events (AE) following fRT. Results: Our cohort included 137 meningiomas, 21 of which progressed after fRT (median PFS 3.45 years). Progressive meningiomas had a larger median gross tumor volume (GTV) compared to those that remained stable (19.1 cm3 vs 9.6 cm3, p = 2.86 × 10-2). GTV > 11.27 cm3 was independently predictive of progression and larger GTV was associated with higher risk of significant (grades 3/4) AE following fRT. Cavernous sinus and optic nerve sheath meningiomas had overall excellent outcomes post-fRT. Conclusions: We present a large cohort of meningiomas treated with primary fRT and find GTV and anatomic location to be key predictors of outcome, adding to the complex treatment considerations for this heterogeneous disease.

4.
Radiother Oncol ; 188: 109861, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37619659

RESUMO

BACKGROUND: Aside from surgical resection, the only standard of care treatment modality for meningiomas is radiotherapy (RT). Despite this, few studies have focused on identifying clinical covariates associated with failure of fractionated RT following surgical resection (fRT), and the timing of fRT following surgery still remains controversial (adjuvant versus salvage fRT). We assessed the outcomes of the largest, multi-institutional cohort of surgically resected meningiomas treated with subsequent adjuvant and salvage fRT to identify factors associated with local freedom from recurrence (LFFR) over 3-10 years post-fRT and to determine the optimal timing of fRT. METHODS: Patients with intracranial meningiomas who underwent surgery and fRT between 1997 and 2018 were included. Primary endpoints were radiographic recurrence/progression and time to progression from the completion of fRT. RESULTS: 404 meningiomas were included for analysis. Of these, 167 (41.3%) recurred post-fRT. Clinical covariates independently associated with worse PFS post-fRT included receipt of previous RT to the meningioma, having a WHO grade 3 meningioma or recurrent meningioma, the meningioma having a higher MIB1-index or brain invasion on pathology, and older patient age at diagnosis. Subgroup analysis identified higher MIB1-index as a histological factor associated with poorer LFFR in WHO grade 2 meningiomas. 179 patients underwent adjuvant RT shortly after surgery whereas 225 patients had delayed, salvage fRT after recurrence/progression. Following propensity score matching, patients that underwent adjuvant fRT had improved LFFR post-fRT compared to those that received salvage fRT. CONCLUSION: There is a paucity of clinical factors that can predict a meningioma's response to fRT following surgery. Adjuvant fRT may be associated with improved PFS post-fRT compared to salvage fRT. Molecular biomarkers of RT-responsiveness are needed to better inform fRT treatment decisions.

5.
Med Pharm Rep ; 95(1): 59-64, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35720244

RESUMO

Background: Anal fistula is often considered to be a dilemma because of the need to maintain a fine balance between postoperative incontinence and recurrence. We tried to find whether apprehension of causing incontinence should stop us from performing fistulectomy. The aim of this study was to determine whether fistulectomy was associated with increased rate of fecal incontinence and recurrence, compared to other procedures used for the treatment of anal fistula. Methods: It was a prospective, single center, observational study. All patients with anal fistula operated at a tertiary care teaching institute over a period of two years were included in the study. Recurrence rates and fecal incontinence were compared between patients subjected to fistulectomy and other procedures for treatment of fistula in ano. Results: A total of 124 patients with anal fistula were included. 92.8% patients were ≤ 60 years of age with high male preponderance (89.5%). Perineal discharge was the commonest complaint (95.96%). Intersphincteric (47.58%) followed by transphincteric fistulas (45.16%) accounted for the majority of fistulas. Fistulectomy was the most common procedure, performed in 90 (72.58%) patients. Incontinence occurred in 8/90 (8.88%) from the fistulectomy group and 2/34 (5.9%) patients in other surgery group, p=0.726. Recurrence occurred in 8/90 (8.88%) from the fistulectomy group and 8/34 (23.5%) patients from other surgery group, p=0.038. Overall rates of incontinence and recurrence were 8.1% and 12.9% respectively. Conclusion: Fistulectomy, as compared to other procedures, results in less chances of recurrence without compromising continence.

6.
Global Spine J ; 11(1_suppl): 23S-29S, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33890805

RESUMO

STUDY DESIGN: Narrative review. OBJECTIVES: We aim to describe current progress in the application of artificial intelligence and machine learning technology to provide automated analysis of imaging in patients with spinal disorders. METHODS: A literature search utilizing the PubMed database was performed. Relevant studies from all the evidence levels have been included. RESULTS: Within spine surgery, artificial intelligence and machine learning technologies have achieved near-human performance in narrow image classification tasks on specific datasets in spinal degenerative disease, spinal deformity, spine trauma, and spine oncology. CONCLUSION: Although substantial challenges remain to be overcome it is clear that artificial intelligence and machine learning technology will influence the practice of spine surgery in the future.

7.
Plant Physiol ; 106(4): 1359-1365, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12232413

RESUMO

The halotolerant alga Dunaliella salina grows in saline conditions as varied as 0.5 and 5 M NaCl, maintaining throughout this range a low intracellular ion concentration. To discover factors potentially involved in ionic homeostasis, we grew cells in media with different salinities or osmolarities and compared their protein profiles. The comparisons indicated that the amount of a 60-kD protein, p60, greatly increased with an increase in salinity and was moderately enhanced when NaCl was substituted with iso-osmotic glycerol. Cells transferred from low to high NaCl or from high glycerol to iso-osmotic NaCl media transiently ceased to grow, and resumption of growth coincided approximately with an increase in p60. The protein, extracted from a plasma membrane fraction, was purified to homogeneity. Anti-p60 antibodies cross-reacted with a 60-kD protein in Dunaliella bardawil. Immunoelectron microscopy of D. salina cell sections indicated that p60 was exclusively located in the plasma membrane. Its induction by salt, the correlation between its accumulation and growth resumption in high concentrations of salt, and its plasma membrane localization suggest the possibility that p60 could play a role in ionic homeostasis in conditions of high salinity, although different types of function could also be considered.

8.
Plant Physiol ; 110(4): 1405-1411, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12226269

RESUMO

The unicellular green alga Dunaliella bardawil exhibits typical responses to excessive light when starved for sulfate under normal light (60 [mu]E m-2 s-1) but not under low light (14 [mu]E m-2 s-1). Algae were analyzed during several days of sulfate starvation for nonphotochemical quenching of chlorophyll fluorescence in the absence or presence of the uncouplers SF-6847 (SF) or carbonyl cyanide p- trifluoromethoxyphenyl hydrazone. Parallel analyses followed two light-stress responses: (a) violaxanthin conversion to zeaxanthin and (b) accumulation of Cbr, a protein analogous to plant early-light-induced proteins and implicated in zeaxanthin binding. In cells starved under normal light SF inhibited nonphotochemical quenching during the first 24 h, but not from 40 h onward. In cells starved under low light SF inhibited nonphotochemical quenching throughout the starvation period. Under normal light accumulation of zeaxanthin was nearly maximal by 24 h, but Cbr was fully induced only by 40h. Under low light zeaxanthin accumulated slowly but no Cbr was evident. These results suggest that during exposure to excessive light, the initial pH gradient-dependent, Cbr-independent mode of nonphotochemical quenching is modified to become less dependent on pH gradient and requires Cbr.

9.
Artigo em Inglês | MEDLINE | ID: mdl-26245616

RESUMO

BACKGROUND: Epilepsy is a common disorder in South Africa and the literature indicates that many patients do not access treatment. The reasons are complex and include a poor knowledge about causes, symptoms, diagnosis and treatment (medical knowledge). This study aimed to assess the medical knowledge of isiZulu-speaking people with epilepsy (PWE) who attend a combination regional and district hospital in the eThekwini district in KwaZulu-Natal Province. METHOD: This was a prospective, cross-sectional, descriptive study. Data were collected using a validated data collection tool for assessing the medical knowledge of PWE and analysed descriptively. RESULTS: The questionnaires were completed by 199 PWE, with the general level of schooling being low and half being unemployed. Knowledge around causes, symptoms, diagnosis and treatments was good, but there were significant gaps in knowledge that may affect morbidity and mortality. DISCUSSION: The findings will serve as a useful guide to develop both preventive and educational interventions to enhance knowledge around the causes and treatment of epilepsy in this population. It is important that such interventions also consider family and healthcare providers. CONCLUSION: There were considerable gaps in the medical knowledge of isiZulu-speaking PWE's, indicating the need for an educational intervention to improve their understanding of epilepsy. Further research is needed-using a range of tools to ensure that the data is reliable and valid-if the results are to be generalisable to the rest of the province and South Africa.


Assuntos
Epilepsia , Conhecimentos, Atitudes e Prática em Saúde , Grupos Populacionais/psicologia , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , África do Sul , Inquéritos e Questionários , Adulto Jovem
10.
Gene ; 27(3): 315-22, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6428978

RESUMO

When a cDNA coding for the kappa light chain (L-321) from the mouse MOPC321 myeloma was cloned into Escherichia coli, L-321 antigens were found in both cytoplasmic and periplasmic fractions. In cells synthesizing the intact chain, starting with its signal peptide, the periplasm contained a mature-size immunoglobulin indicating that the eukaryotic signal peptide can initiate secretion and be processed. When the entire cDNA for L-321 (including its signal peptide) was inserted in the gene for bacterial beta-lactamase, processing cleaved only the first bacterial signal sequence of the hybrid protein synthesized. Removal of the beta-lactamase signal peptide was also observed with another beta-lactamase-L-321 hybrid which did not include the immunoglobulin signal peptide and the adjacent part of the variable region. The two hybrid proteins may, however, differ in their mode of secretion.


Assuntos
Escherichia coli/genética , Cadeias Leves de Imunoglobulina/genética , Clonagem Molecular , Escherichia coli/imunologia , Cadeias Leves de Imunoglobulina/imunologia , Plasmídeos , Processamento de Proteína Pós-Traducional , beta-Lactamases/genética
11.
Gene ; 35(1-2): 1-9, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3896931

RESUMO

Biological nitrogen fixation is catalyzed by nitrogenase, an enzyme complex exclusive to prokaryotes. We used the yeast Saccharomyces cerevisiae to study the synthesis, and subsequently the assembly, of nitrogenase components in a eukaryote. Here, the Klebsiella pneumoniae nifH gene, encoding the subunit of the Fe protein (Kp2) component of nitrogenase, was expressed in S. cerevisiae from the yeast ADHI promoter. The nifH gene product, detected in yeast by immunoblot analysis with anti-Kp2 antibodies, exhibited the same electrophoretic mobility in SDS-polyacrylamide gels as that of the Kp2 subunit synthesized in K. pneumoniae. Estimates of Kp2 antigen and assays of beta-galactosidase activity specified by nifH'-'lacZ fusions showed that the level of nifH product was similar in anaerobically and aerobically grown yeast, but varied with different transforming plasmids and in various haploid and diploid yeast strains. A cistron located downstream to nifH in a transcript resembling the polycistronic mRNA of the nifHDKY operon in K. pneumoniae is not translated in yeast.


Assuntos
Nitrogenase/genética , Saccharomyces cerevisiae/genética , Regulação da Expressão Gênica , Genes Bacterianos , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Fixação de Nitrogênio , Óperon , Consumo de Oxigênio , Plasmídeos , Biossíntese de Proteínas , Saccharomyces cerevisiae/metabolismo , Transformação Genética
12.
FEBS Lett ; 197(1-2): 93-8, 1986 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-3005048

RESUMO

Electrophoretic resolution of topoisomers was used to compare the in vivo superhelicity of recombinant plasmids containing a fragment of cDNA for an immunoglobulin light chain, cloned in the two possible orientations into the BamHI site of pBR313 or pBR322. Previously, frequent transpositions of IS1 or IS5 were observed into the sequence upstream to the cloned fragment in recombinants in one orientation [(+) plasmids] but not in recombinants in the opposite, (-) orientation [(1982) Nucleic Acids Res. 10, 4525-4542]. The results of the present analyses show that, on average, (-) plasmids are less negatively supercoiled than (+) plasmids, or pBR322. These results suggest that primary sequence rearrangements in plasmids could affect their in vivo topological state, and consequently, perhaps, their effectiveness as recipients of transposable elements.


Assuntos
DNA Recombinante , DNA Super-Helicoidal , Plasmídeos , Sequência de Bases , DNA , Elementos de DNA Transponíveis , Eletroforese em Gel de Ágar , Escherichia coli/genética , Cadeias Leves de Imunoglobulina/genética
13.
Biosci Rep ; 7(12): 941-8, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3331121

RESUMO

A new homologous, cell-free system for protein synthesis has been devised for use with ribosomes and elongation factors from Aspergillus nidulans. Ribosome preparations from strains with either the suaA101 or suaC109 mutations have a higher misreading ratio (non-cognate:cognate amino acid incorporation) in the presence of hygromycin than controls. They can be classed as fidelity mutants. These results also prove that the mutations must be in genes coding for ribosomal proteins or enzymes which modify ribosomal proteins post-translationally. Alternatively, the genes could code for translation factors.


Assuntos
Aspergillus nidulans/genética , Cinamatos , Fenótipo , Ribossomos , Supressão Genética , Higromicina B/análogos & derivados , Higromicina B/farmacologia , Mutação , Fenilalanina/metabolismo
14.
Carbohydr Res ; 41: 227-33, 1975 May.
Artigo em Inglês | MEDLINE | ID: mdl-1137838

RESUMO

The mercapto groups of cellulose xanthate can reversibly form disulphide bridges with L-cysteine. This property has been utilised for the immobilisation of a protein and an enzyme. These macromolecules, as polythiol derivatives, formed disulphide linkages with the matrix without serious disturbance of their active sites, became firmly bound to the xanthate, and were not eluted by normal washing conditions. Cellulose xanthate is a cheap, easily prepared matrix which permits a simple coupling reaction. The immobilisation process is selectively reversible.


Assuntos
Celulose/análogos & derivados , Enzimas , Proteínas , Xantinas , Sítios de Ligação , Cisteína , Dissulfetos , Métodos , Ligação Proteica , Solubilidade
15.
J Forensic Sci ; 45(1): 158-60, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10641930

RESUMO

DNA extracted from fingernail clippings of victims in forensic cases is a possible source of DNA from the perpetrator in cases where victims struggled or defended themselves. The source of this DNA on a victim's fingernails could possibly originate from contact with the suspect's blood, saliva, semen or scratched skin. In this technical note we evaluate the relevance of routine DNA typing of fingernail clippings in the forensic biology laboratory when, in real casework, normally only small quantities of nail material is sent. This was carried out by extracting DNA from fingernail clippings from a number of volunteers, before and after aggressively scratching other volunteers. No blood was drawn from the scratching, but skin flakes were observed under the nails before cutting and subsequent DNA typing. The DNA extracted was then typed using the STR systems: HUMTHO1, HUMTPOX and HUMCSF1PO (CTT triplex) and the system of D1S80. These profiles were compared with profiles achieved by similar typing of buccal swabs as a reference from each volunteer. In this study, the profile detected from each volunteer's clippings was the same before and after scratching, and matched the profile of the corresponding volunteer as defined by typing each volunteer's reference buccal swab. Fingernail clippings that are sent to our lab in actual casework are usually so small that additional treatment by swabbing or removing debris from below the clipping is not possible. For this reason, in this simulation the entire clippings were used for DNA extraction, to maximize the possibility of finding an additional profile. In conclusion, the findings from this study show that although the profiles obtained when typing fingernail clippings are those of the donors themselves, we suggest that typing of fingernail clippings should be carried out in forensic cases only when relevant. We would suggest that fingernail clippings not be routinely sent to the biology laboratory as items of evidence to be tested.


Assuntos
Medicina Legal/métodos , Unhas/patologia , Análise de Sequência de DNA , Humanos
16.
J Forensic Sci ; 45(2): 445-6, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10782971

RESUMO

Two cases of threatening letters with their accompanying envelopes were received to the Division of Forensic Identification unit of the Israel Police. The envelopes, including the stamps, and the letters were initially examined for latent fingerprints by the DFO reagent, known to cause degradation of DNA. Although no latent fingerprints could be visualized on any of the items, the biology laboratory using organic DNA extraction, was successful in defining genetic profiles from all the items employing six STR loci, even after treatment with DFO. In a controlled experiment, a known donor attached a stamp, by licking, to an envelope. This item was treated with DFO and then profiled using STR loci. The results showed that previous DFO treatment on the control stamp before DNA analysis had no negative effects on obtaining the DNA profile of the known donor using STR loci.


Assuntos
Compostos Aza/farmacologia , Impressões Digitais de DNA/normas , Dermatoglifia , Medicina Legal/métodos , Sequências de Repetição em Tandem/genética , Crime , Humanos , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Manejo de Espécimes
17.
J Forensic Sci ; 45(3): 687-8, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10855979

RESUMO

An exhibit that is often received for examination in cases of robbery or terrorist activity is adhesive tape. This type of exhibit can often, but not always, be successfully processed for fingerprints. The question arises whether or not it is possible to extract and type DNA after the tape has been sequentially processed for fingerprints. In this work, various donors left fingerprints on the adhesive side of tapes. The tapes were then sequentially processed for fingerprints using an alternate light source, cyanoacrylate fuming, and staining with BY-40 and then crystal violet. DNA was subsequently successfully extracted, amplified and typed for six STR loci.


Assuntos
DNA/isolamento & purificação , Dermatoglifia , Repetições de Microssatélites/genética , Adesivos , DNA/análise , Medicina Legal/métodos , Humanos , Reação em Cadeia da Polimerase , Manejo de Espécimes , Violência
18.
J Forensic Sci ; 39(4): 1120-5, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8064273

RESUMO

Two wall hangings, from the time of the Second World War, were reportedly made from human hair. Laboratory examination of the hangings confirmed this fact. Fibers, holding the wall hangings together, and the weave of the hangings were also examined. Results and implications of the findings are discussed.


Assuntos
Arte/história , Cabelo , Holocausto/história , Têxteis/história , Animais , História do Século XX , Humanos , Israel , Itália , Têxteis/análise
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