Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
Pediatr Blood Cancer ; 71(2): e30760, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37962283

RESUMO

INTRODUCTION: The objectives of this study were to evaluate the prognostic impact of pre-referral surgical resection of Wilms tumor (WT) performed at non-oncology centers, and to strategize an improved care plan for this very curable pediatric tumor. METHODS: In this study conducted in a large pediatric cancer center in Pakistan, we retrospectively reviewed the electronic medical records (EMR) of 149 patients with unilateral WT from September 2008 to August 2017. Based on treatment approach, patients were categorized into two groups: (i) pre-referral tumor resection (PTR: n = 75), and (ii) post-neoadjuvant chemo nephrectomy (PCN: n = 74). RESULTS: The proportion of metastatic disease in PTR and PCN groups was 33.3% and 35.1%, respectively. In the PTR subset, median time to admission after PTR was 5 weeks (mean 11, SEM 2.8, range: 2-202) weeks, with 53.3% (n = 40) presenting more than 4 weeks after PTR. Twenty patients had no cross-sectional imaging prior to PTR and underwent surgery after abdominal ultrasound only. On baseline imaging at our center, 58.7% (n = 44) of the PTR group had radiologically evaluable disease (four metastases only, 19 local residual tumor only, 21 both localized tumor and visible metastases). Disease staging was uncertain in 23 patients because of no or inadequate histology specimens and/or lymph node sampling in patients with no evaluable disease. Statistically significant differences were recorded for the two subsets regarding tumor volume, extent and nodularity, renal vein and renal sinus involvement, lymph node status, tumor rupture and histopathologic features, and tumor stage, with a 10-year event-free survival (EFS) for PCN and PTR of 74.3% and 50.7%, respectively (p < .001). In the PTR group, EFS for those presenting within 4 weeks and later was 91.4% versus 15.0%, respectively (p < .0001). CONCLUSION: Suboptimal pre-referral surgical intervention results in poor survival outcomes in unilateral WT. Our findings highlight the need for a comprehensive action plan for educating healthcare professionals engaged in WT diagnosis and referral process. PCN in a multidisciplinary team approach can reduce surgical morbidity and seems to be a better strategy to improve the survival rates in low-resource settings.


Assuntos
Neoplasias Renais , Tumor de Wilms , Criança , Humanos , Prognóstico , Neoplasias Renais/patologia , Estudos Retrospectivos , Estadiamento de Neoplasias , Tumor de Wilms/patologia , Nefrectomia/métodos
2.
Biochem Genet ; 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38110774

RESUMO

Breast cancer is a significant health challenge for women globally, including the Pakistani population. Numerous pathways and small molecules like noncoding ribonucleotides are implicated in breast cancer development and progression. Among these, lncRNAs, have garnered considerable attention due to their role in breast cancer tumorigenesis and metastasis. In the current study involving 52 mammary tumor samples from the Pakistani population, the expression of lncRNA MALAT1 (metastasis associated lung adenocarcinoma transcript 1) was studied via RT-PCR (Real-Time polymerase chain reaction). In addition, PI3K/AKT/mTOR pathway expression was also assessed through RT-PCR and immunohistochemistry in breast cancer patient samples. The study also investigated the cross-talk of lncRNA MALAT1 and PI3K pathway genes by inhibiting it with PI3K inhibitor (LY294002) in MDA-MB-231 cell line. Furthermore, lncRNA MALAT1 was silenced in MDA-MB-231 cells using siRNA to determine its impact on breast cancer proliferation and metastasis. The results revealed an upregulated expression of MALAT1 and PI3K/AKT/mTOR pathway genes in grade II and III breast tissue samples before chemotherapy. The proliferation, growth, and invasion of breast cancer cells were significantly reduced upon MALAT1 silencing in MDA-MB-231. Further, its downregulation substantially reduced the PI3K pathway expression levels at mRNA and protein levels. In conclusion, the current study suggests that MALAT1 could serve as a therapeutic target for breast cancer, underscoring its role in breast cancer proliferation and metastasis. Moreover, the study proposes a mechanism of action of MALAT1, demonstrating that its inhibition can reduce the expression of the PI3K/AKT/mTOR axis. These findings emphasize the potential significance of targeting MALAT1 as a therapeutic strategy for breast cancer, and further exploration of this interaction is warranted to gain deeper insight into the molecular mechanism of this lncRNA.

3.
Expert Rev Neurother ; 23(9): 845-851, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37602687

RESUMO

INTRODUCTION: Having lived through a pandemic and witnessed how regulatory approval processes can evolve rapidly; it is lamentable how we continue to rely on symptoms/signs and nerve conduction as primary endpoints for clinical trials in DPN. AREAS COVERED: Small (Aδ and C) fibers are key to the genesis of pain, regulate skin blood flow, and play an integral role in the development of diabetic foot ulceration but continue to be ignored. This article challenges the rationale for the FDA insisting on symptoms/signs and nerve conduction as primary endpoints for clinical trials in DPN. EXPERT OPINION: Quantitative sensory testing, intraepidermal nerve fiber density, and especially corneal confocal microscopy remain an after-thought, demoted at best to exploratory secondary endpoints in clinical trials of diabetic neuropathy. If pharma are to be given a fighting chance to secure approval for a new therapy for diabetic neuropathy, the FDA needs to reassess the evidence rather than rely on 'opinion' for the most suitable endpoint(s) in clinical trials of diabetic neuropathy.


Assuntos
Diabetes Mellitus , Neuropatias Diabéticas , Humanos , Neuropatias Diabéticas/tratamento farmacológico , Fibras Nervosas , Condução Nervosa , Microscopia Confocal
4.
BMC Pregnancy Childbirth ; 23(1): 431, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37301973

RESUMO

OBJECTIVES: Explore health-care seeking behaviour among couples with pregnancies at-risk of monogenic disorders and compare time duration for obtaining Prenatal Genetic Test (PGT) results based on (i) amniocentesis and Chorionic Villus Sampling (CVS) (ii) in-house testing and out-sourced testing. Report the spectrum of monogenic disorders in our cohort. METHODS: Medical records of women consulting prenatal genetic counselling clinic at Aga Khan University Hospital, Karachi from December-2015 to March-2021 with history of miscarriage or a monogenic disorder in previous children were reviewed. RESULTS: Forty-three pregnancies in 40 couples were evaluated, 37(93%) were consanguineous. Twenty-five (63%) couples consulted before and 15(37%) after conception. Thirty-one (71%) pregnancies underwent CVS at the mean gestational age of 13-weeks and 6-days ± 1-week and 3-days and amniocentesis at 16-weeks and 2-days ± 1-week and 4-days. PGT for 30 (70%) pregnancies was outsourced. The mean number of days for in-house PGT was 16.92 ± 7.80 days whereas for outsourced was 25.45 ± 7.7 days. Mean duration from procedure to PGT result was 20.55 days after CVS compared to 28.75 days after amniocentesis. Eight (18%) fetuses were homozygous for disease-causing variant for whom couples opted for termination of pregnancy (TOP). Twenty-six monogenetic disorders were identified in 40 families. CONCLUSION: Proactive health-care seeking behaviour and TOP acceptance is present amongst couples who have experienced a genetic disorder.


Assuntos
Amniocentese , Países em Desenvolvimento , Gravidez , Criança , Feminino , Humanos , Lactente , Atenção Terciária à Saúde , Amostra da Vilosidade Coriônica , Testes Genéticos
5.
J Biomol Struct Dyn ; 40(17): 7829-7851, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-33764266

RESUMO

Berberis lyceum and Fumaria indica are two Pakistani indigenous herbal medicines used to treat liver infections, including hepatitis C virus (HCV). This study aimed to evaluate the cytotoxicity, and antioxidant activity of these plant extracts and computationally screen their selected phytoconstituents as HCV NS5A inhibitors. The viability of HepG2 cells was assessed 24 h and 48 h post-treatment using colorimetric and dye exclusion methods. Antioxidant properties were examined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH), reducing power, and total antioxidant capacity assays. Seventeen known phytochemicals identified from each plant were docked into the active binding site of HCV NS5A protein. The top hit ligands were analyzed for their druglikeness properties and the indices of absorption, distribution, metabolism, elimination, and toxicity (ADMET). The results showed that both plant extracts were non-toxic (CC50 > 200 µg/ml). The IC50 values of DPPH-radical scavenging activity were 51.02 ± 0.94 and 62.91 ± 1.85 µg/ml for B. lyceum and F. indica, respectively. They also exhibited reducing power and total antioxidant capacity.The phytochemicals were identified as potent HCV NS5A inhibitors with good druglikeness and ADMET properties. Six of the docked phytochemicals exhibited higher binding scores (-17.9 to -19.2 kcal/mol) with HCV NS5A protein than the standard drug, daclatasvir (-17.2 kcal/mol). Molecular dynamics (MD) simulation confirmed the stability of two compounds, berbamine and paprafumine at 100 ns with active site of HCV NS5A protein. The identified compounds through molecular docking and MD simulation could have potential as HCV NS5A inhibitor after further validation.


Assuntos
Berberis , Fumaria , Hepatite C , Antioxidantes/farmacologia , Antivirais/química , Berberis/metabolismo , Hepacivirus/metabolismo , Simulação de Acoplamento Molecular , Compostos Fitoquímicos/metabolismo , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia , Proteínas não Estruturais Virais/química
6.
PLoS One ; 16(7): e0255243, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34297787

RESUMO

Breast cancer poses a serious health risk for women throughout the world. Among the Asian population, Pakistani women have the highest risk of developing breast cancer. One out of nine women is diagnosed with breast cancer in Pakistan. The etiology and the risk factor leading to breast cancer are largely unknown. In the current study the risk factors that are most pertinent to the Pakistani population, the etiology, molecular mechanisms of tumor progression, and therapeutic targets of breast cancer are studied. A correlative, cross-sectional, descriptive, and questionnaire-based study was designed to predict the risk factors in breast cancer patients. Invasive Ductal Carcinoma (90%) and grade-II tumor (73.2%) formation are more common in our patient's data set. Clinical parameters such as mean age of 47.5 years (SD ± 11.17), disturbed menstrual cycle (> 2), cousin marriages (repeated), and lactation period (< 0.5 Y) along with stress, dietary and environmental factors have an essential role in the development of breast cancer. In addition to this in silico analysis was performed to screen the miRNA regulating the TGF-beta pathway using TargetScanHuman, and correlation was depicted through Mindjet Manager. The information thus obtained was observed in breast cancer clinical samples both in peripheral blood mononuclear cells, and biopsy through quantitative real-time PCR. There was a significant dysregulation (**P>0.001) of the TGF-ß1 signaling pathway and the miRNAs (miR-29a, miR-140, and miR-148a) in patients' biopsy in grade and stage specifically, correlated with expression in blood samples. miRNAs (miR-29a and miR-140, miR-148a) can be an effective diagnostic and prognostic marker as they regulate SMAD4 and SMAD2 expression respectively in breast cancer blood and biopsy samples. Therefore, proactive therapeutic strategies can be devised considering negatively regulated cascade genes and amalgamated miRNAs to control breast cancer better.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , MicroRNAs/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Adulto , Neoplasias da Mama/epidemiologia , Carcinoma Ductal de Mama/epidemiologia , Feminino , Humanos , MicroRNAs/genética , Pessoa de Meia-Idade , Paquistão , Proteína Smad2/genética , Proteína Smad2/metabolismo , Proteína Smad4/genética , Proteína Smad4/metabolismo , Fator de Crescimento Transformador beta/genética
7.
Cureus ; 13(5): e15132, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34159034

RESUMO

Primary cutaneous CD8+ aggressive epidermotropic cytotoxic T-cell lymphoma (CD8+ PCAECTL) is an extremely rare neoplasm with a poor prognosis. Chemotherapy typically does not result in a sustained response, and hematopoietic stem cell transplant (HSCT) is the only therapy that has been shown to produce a durable response of any kind. Here, we report a case of a 25-year-old previously healthy male who presented with a painful ulcerative lesion on the bottom of his right great toe and local lymphadenopathy. The biopsy of the lesion was consistent with CD8+ PCAECTL. He received immediate chemotherapy followed by matched related donor HSCT (MRD-HSCT) and remained in complete remission (CR) for eight years post-transplant, longer than any CR reported in the literature. In conclusion, our report provides clinical evidence that early transplant consult and donor search is one of the key factors in the management of CD8+ PCAECTL.

8.
J Ethnopharmacol ; 272: 113938, 2021 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-33610708

RESUMO

ETHNOBOTANICAL RELEVANCE: Tectona grandis L.f (or syn: Jatus grandis (L.f.) Kuntze Revis), from family Lamiaceae, also known as Teak, is widely recognized in ayurvedic system of medicine and confer curative potential against inflammation, liver disorders, biliousness, diabetes, bronchitis, leprosy and dysentery. Its leaves are rich source of edible food colorant and reported nontoxic for liver and various organs. AIM OF STUDY: Hepatic injury progression to liver cirrhosis and cancer is a serious health issue across the world. Currently, anti-fibrotic therapeutic options are limited and expensive with no FDA approved direct anti-hepato-fibrotic drug validated in clinic. Thus, the aim of this study was to understand ameliorative effect of Tectona grandis L.f, leaves in early liver fibrosis. METHOD AND RESULTS: C57BL/6 mice suffering from CCl4 induced liver injury, were orally administered at three different doses (50, 100 & 200 mg/kg) of Tectona grandis L.f, leaf extract, thrice a week, up to 4 and 8 weeks. Anti-fibrotic effect was evaluated through animal body/liver weight measurements, serological tests (AST, ALT, GSH, MDA and LDH assays), tissue hydroxyproline content, and histochemical analysis (H&E, Masson trichrome, Sirius red and αSMA localization). Moreover, transcriptional and post-transcriptional expression of fibrosis associated biomarkers and TGF-ß/Smad cascade were analyzed. It was observed that 100 mg/kg dose optimally downregulated TGF-ß1/Smad2 with upregulation of Smad7 and regulated αSMA, Col 1, PDGF, TIMP1 and MMP3 expression, post 8 weeks of treatment. In addition, MMP3/TIMP1 ratio was upregulated to 0.7, 2.5 and 1.7 fold at 50 mg/kg, 100 mg/kg & 200 mg/kg treatments respectively, in comparison to untreated liver fibrosis models. The extract contains gallic acid, caffeic acid, sinapinic acid and myricetin when analyzed through high performance liquid chromatography. CONCLUSION: Tectona grandis L.f, leaves have potential to ameliorate liver fibrosis induced by CCl4 in mice via modulation of TGF-ß1/Smad pathway and upregulated MMP3/TIMP1 ratio.


Assuntos
Lamiaceae/química , Cirrose Hepática/prevenção & controle , Metaloproteinase 3 da Matriz/metabolismo , Substâncias Protetoras/farmacologia , Substâncias Protetoras/intoxicação , Transdução de Sinais/efeitos dos fármacos , Proteína Smad2/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Tetracloreto de Carbono/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Colágeno/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Células Hep G2 , Células Estreladas do Fígado/efeitos dos fármacos , Humanos , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Metaloproteinase 3 da Matriz/genética , Camundongos Endogâmicos C57BL , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Substâncias Protetoras/química , Proteína Smad2/genética , Inibidor Tecidual de Metaloproteinase-1/genética , Transaminases/sangue , Fator de Crescimento Transformador beta/genética , Células Vero
9.
Front Pain Res (Lausanne) ; 2: 725363, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35295436

RESUMO

Neuropathic pain has multiple etiologies, but a major feature is small fiber dysfunction or damage. Corneal confocal microscopy (CCM) is a rapid non-invasive ophthalmic imaging technique that can image small nerve fibers in the cornea and has been utilized to show small nerve fiber loss in patients with diabetic and other neuropathies. CCM has comparable diagnostic utility to intraepidermal nerve fiber density for diabetic neuropathy, fibromyalgia and amyloid neuropathy and predicts the development of diabetic neuropathy. Moreover, in clinical intervention trials of patients with diabetic and sarcoid neuropathy, corneal nerve regeneration occurs early and precedes an improvement in symptoms and neurophysiology. Corneal nerve fiber loss also occurs and is associated with disease progression in multiple sclerosis, Parkinson's disease and dementia. We conclude that corneal confocal microscopy has good diagnostic and prognostic capability and fulfills the FDA criteria as a surrogate end point for clinical trials in peripheral and central neurodegenerative diseases.

10.
Artigo em Inglês | MEDLINE | ID: mdl-32697756

RESUMO

Objectives To review red algae bioactive compounds and their pharmaceutical applications. Content Seaweed sources are becoming attractive to be used in health and therapeutics. Among these red algae is the largest group containing bioactive compounds utilized in cosmetic, pharmaceutical, food industry, manure and various supplements in food formula. Various significant bioactive compounds such as polysaccharides (aginate, agar, and carrageenan), lipids and polyphenols, steroids, glycosides, flavanoids, tannins, saponins, alkaloids, triterpenoids, antheraquinones and cardiac glycosides have been reported in red algae. The red algae have rich nutritional components Different polysaccharides of red algae possess the antiviral potential namely agarans, carrageenan, alginate, fucan, laminaran and naviculan. Sulfated polysaccharides and carraginans of red algae are rich source of soluble fibers which can account for antitumor activities depending upon chemistry of various secondary metabolites and metabolism of cell line. Flavons-3-ols containing catechins from many red algae block the telomerase activity in colon cancer cells. Contraceptive agents were tested from red algae as a source for post-coital. Lectin of red algae showed pro-healing properties and anti-ulcerogenic activities. Carragenates from red algae also conferred a positive influence on diabetes. Red algae depicted a reducing effect on plasma lipids and obesity. Porphyran from red alga can act as anti-hyperlipidemic agent also reduces the apolipoprotein B100 via suppression of lipid synthesis in human liver. Summary The polyphenolic extracts of Laurencia undulate, Melanothamnus afaqhusainii and Solieria robusta extract show anti-inflammatory effects against multiple genera of devastating fungi. Antioxidants such as phlorotannins, ascorbic acids, tocopherols, carotenoids from red algae showed toxicity on some cancer cells without side effects. Red algae Laurencia nipponica was found insecticidal against mosquito larvae. Red algae fibers are very important in laxative and purgative activities. Gracilaria tenuistipitat resisted in agricultural lands polluted with cadmium and copper. Outlook In the recent decades biotechnological applications of red algae has been increased. Polysaccharides derived from red algae are important tool for formulation of drugs delivery system via nanotechnology.

11.
J Pak Med Assoc ; 70(5): 920-922, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32400754

RESUMO

Surgical repair of transposition of great arteries has undergone various evolutionary changes over the years. The initial of these treatment options was atrial septectomy followed by atrial switch and the current preferred treatment option is arterial switch operation worldwide. Due to various reasons, like lack of medical and surgical expertise atrial switch operation was commonly in practice in developing countries until few years back. Pregnancy in a patient with history of atrial switch operation poses a unique haemodynamic challenge. We report the case of a successful pregnancy in a 26 years old lady who had undergone Mustard repair surgery in the past in Pakistan.


Assuntos
Transposição das Grandes Artérias , Cesárea/métodos , Complicações Cardiovasculares na Gravidez , Transposição dos Grandes Vasos/cirurgia , Insuficiência da Valva Tricúspide , Disfunção Ventricular Direita , Adulto , Transposição das Grandes Artérias/efeitos adversos , Transposição das Grandes Artérias/métodos , Ecocardiografia/métodos , Procedimentos Cirúrgicos Eletivos/métodos , Feminino , Humanos , Poli-Hidrâmnios/diagnóstico , Poli-Hidrâmnios/fisiopatologia , Gravidez , Complicações Cardiovasculares na Gravidez/diagnóstico , Complicações Cardiovasculares na Gravidez/fisiopatologia , Resultado da Gravidez , Gravidez de Alto Risco , História Reprodutiva , Transposição dos Grandes Vasos/diagnóstico , Insuficiência da Valva Tricúspide/diagnóstico , Insuficiência da Valva Tricúspide/etiologia , Ultrassonografia Pré-Natal/métodos , Disfunção Ventricular Direita/diagnóstico , Disfunção Ventricular Direita/etiologia
12.
Life Sci ; 240: 117104, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31783054

RESUMO

Xanthophylls constitute a major part of carotenoids in nature. They are an oxidized version of carotenoid. Xanthophyll has widely drawn scientists' attentions in terms of its functionality, bioavailability and diversity. An assortment of xanthophyll varieties includes lutein, zeaxanthin, ß-cryptoxanthin, capsanthin, astaxanthin, and fucoxanthin. Chemically, lutein and zeaxanthin are dipolar carotenoids with hydroxyl groups at both ends of their molecules that bestow hydrophilic properties to them. Hydrophilic affinity in lutein and zeaxanthin makes better bioavailability in reaction with singlet oxygen in water phase, whereas non-polar carotenoids have shown to have less efficiency in scavenging free radicals. Xanthophylls have been studied for their effects in a wide variety of diseases including neurologic, ophthalmologic, oral, allergic and immune diseases. This review highlights pharmaco-pharmaceutical applications of xanthophylls as well asits drug interactions with beta-carotene. Different types of xanthophylls have been shown to have neuroprotective effects. Fucoxanthin demonstrated potent antiplasmodial activity. Lutein and zeaxanthin prevent the progression of age related macular degeneration. They have also demonstrated promising effects on uveitis, retinitis pigmentosa, scleritis, cataracts, glaucoma, retinal ischemia and choroideremia. Astaxanthin showed to have skin protecting effects against ultraviolet light injury. Astaxanthin have anti-allergic activity against the contact dermatitis especially to treat the patients having adverse reactions induced by steroids. Astaxanthin has been reported to exert beneficial effects in preventing oral lichen planus and early stage cancers. ß-cryptoxanthin has been considered a good candidate for prevention of bone loss via osteoblastic bone formation and inhibiting osteoclastic bone resorption. There is also some concern that higher dose of xanthophylls may be linked to increased risk of skin cancer and gastric adenocarcinoma. However this increased risk was not statistically significant when adjusted for confounding factors. Further researches including clinical studies are needed to better evaluate the efficacy and safety of xanthophylls in prevention and treatment of different diseases.


Assuntos
Xantofilas/farmacologia , Xantofilas/uso terapêutico , Animais , Humanos , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Prevenção Primária
13.
J Am Chem Soc ; 134(31): 12947-57, 2012 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-22765168

RESUMO

Proton transfer to carbon represents a significant catalytic challenge because of the large intrinsic energetic barrier and the frequently unfavorable thermodynamics. Multiple kinetic isotope effects (KIEs) were measured for acid-catalyzed hydrolysis of the enol ether functionality of enolpyruvylshikimate 3-phosphate (EPSP) as a nonenzymatic analog of the EPSP synthase (AroA) reaction. The large solvent deuterium KIE demonstrated that protonating C3 was the rate-limiting step, and the lack of solvent hydron exchange into EPSP demonstrated that protonation was irreversible. The reaction mechanism was stepwise, with C3, the methylene carbon, being protonated to form a discrete oxacarbenium ion intermediate before water attack at the cationic center, that is, an AH(‡)*AN (or AH(‡) + AN) mechanism. The calculated 3-(14)C and 3,3-(2)H2 KIEs varied as a function of the extent of proton transfer at the transition state, as reflected in the C3-H(+) bond order, nC3-H+. The calculated 3-(14)C KIE was a function primarily of C3 coupling with the movement of the transferring proton, as reflected in the reaction coordinate contribution ((light)ν(‡)/(heavy)ν(‡)), rather than of changes in bonding. Coupling was strongest in early and late transition states, where the reaction coordinate frequency was lower. The other calculated (14)C and (18)O KIEs were more sensitive to interactions with counterions and solvation in the model structures than nC3-H+. The KIEs revealed a moderately late transition state with significant oxacarbenium ion character and with a C3-H(+) bond order ≈0.6.


Assuntos
Éteres/química , Hidrólise , Fosfoenolpiruvato/análogos & derivados , Fosfoenolpiruvato/química , Prótons , Ácido Chiquímico/análogos & derivados , Ácido Chiquímico/química , 3-Fosfoshikimato 1-Carboxiviniltransferase/metabolismo , Radioisótopos de Carbono , Deutério , Cinética , Isótopos de Oxigênio , Teoria Quântica
14.
Eur J Obstet Gynecol Reprod Biol ; 159(1): 91-4, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21839576

RESUMO

Heart disease in pregnancy remains one of the important causes for maternal and fetal mortality and morbidity. Cardiac surgery undertaken in pregnancy presents specific additional issues for both the mother and fetus; especially cardiopulmonary bypass and the factors associated with it. Successful outcome of cardiopulmonary bypass surgery during pregnancy depends upon the multidisciplinary management of the patient, which is frequently under reported from the developing world. We present our experience of two cases where cardiopulmonary bypass surgery for cardiac valve replacement was successfully performed during pregnancy without any maternal or fetal mortality. A review of published literature is also undertaken in order to present evidence based recommendations for undertaking such procedures in pregnancy.


Assuntos
Doenças das Valvas Cardíacas/cirurgia , Implante de Prótese de Valva Cardíaca , Complicações Cardiovasculares na Gravidez/cirurgia , Adulto , Ponte Cardiopulmonar/efeitos adversos , Cesárea , Países em Desenvolvimento , Medicina Baseada em Evidências , Feminino , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Nascido Vivo , Paquistão , Gravidez , Segundo Trimestre da Gravidez , Gravidez de Gêmeos , Nascimento a Termo , Resultado do Tratamento
15.
J Pak Med Assoc ; 59(8): 580-1, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19757713

RESUMO

Chorioangioma is a benign tumour of the placenta consisting of blood vessels and stroma that proliferates beyond normally developing chorionic villi. Most of the small tumours are asymptomatic but large placental tumours are associated with unfavourable outcomes for foetus and mother. We present a case of a 23 year old primigravida who had a large chorioangioma that lead to intrauterine foetal demise. Major complications and diagnostic tools for chrioangioma have been discussed.


Assuntos
Hemangioma/diagnóstico , Doenças Placentárias/diagnóstico , Placenta/patologia , Complicações Neoplásicas na Gravidez/diagnóstico , Adulto , Feminino , Morte Fetal , Hemangioma/patologia , Humanos , Bem-Estar Materno , Doenças Placentárias/patologia , Gravidez , Complicações Neoplásicas na Gravidez/patologia , Ultrassonografia Pré-Natal
16.
J Ayub Med Coll Abbottabad ; 20(4): 18-21, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19999195

RESUMO

BACKGROUND: To prospectively review the clinicopathologic pattern and out come in 15 patients with adolescent ovarian tumours in Military Hospital Rawalpindi between Jan 2004 to Sep 2007. METHODS: All cases of adolescent ovarian tumours reporting to the gynaecology department of Military Hospital Rawalpindi during the period of enrolment. Out of 15 cases 12 were managed surgically. Data was recorded regarding clinical presentation, patient's age, size of tumour, bilaterality, histopathology, staging if tumour was malignant and sites of extra ovarian involvement. All patients were followed up for one year. RESULTS: Majority of patients fell in the subgroup 14-16 year age. Majority harboring ovarian malignancy belonged to subgroup 17-19 years. Clinical presentation in the majority was mass abdomen and abdominal distension. Approach was transcutaneous in 3 (20%), laparoscopic in 2(20%), and open laparotomy in 10 (60%). Frozen section was performed in 3 cases. Histopathology was benign in 11 cases and malignant in 4. In 3 cases cyst fluid was negative for malignancy. In 2 cyst wall biopsy and one patient where entire cyst was removed histopathology revealed benign serous cyst adenoma/luteal cyst (26%). There were 5 cases of dermoid cysts (33.3%), one patient had bilateral dermoids, one malignant and one benign. All 4 malignancies were found to be to non-epithelial on histopathology. One case had surgery twice. Unilateral oopherectomy followed by recurrence and total abdominal hysterectomy and contralateral salpingo-oopherectomy after 2 years. CONCLUSION: This study shows the preponderance of non-epithelial tumours and high percentages of malignant germ cell tumours in adolescents. The incidence of malignant tumours in adolescents is higher than in adults. Early correct diagnosis could be reached by careful physical examination, imaging and tumour markers Surgery should as much as is safely possible be fertility preserving.


Assuntos
Neoplasias Ovarianas/patologia , Adolescente , Fatores Etários , Criança , Feminino , Humanos , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/cirurgia , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA