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1.
Sci Rep ; 14(1): 15804, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982266

RESUMO

The similarity test of ship stiffened plate structures under underwater explosions is a cost-effective and efficient method to evaluate the vitality of ships and guide the design of their shock resistance. This study focuses on the nonlinear impact response model tests of ship stiffened plate structures and their similarity laws with actual ships. The vertical motion of the ship stiffened plate structure is characterized by the Hurst index, and an equivalent relationship between the Hurst index of the model and the prototype is derived from classical similarity law. Based on the Hurst index, a similarity transformation relationship between the strain signals of the model and prototype is established. To verify the conclusions, similarity experiments of underwater explosions were conducted on both the model and the prototype. The original signals were grouped by the natural vibration period to determine the variation of the Hurst index over time. The model experiment strain signals for each natural vibration period were converted and compared with the prototype experiment results to verify the method's effectiveness. Simultaneously, the Hurst index of the stiffened plate structure under explosive shock load and its similarity transformation relationship with the prototype were simulated and analyzed. This provides theoretical and technical support for conducting analogous nonlinear response experiments for ship underwater explosions.

2.
Mymensingh Med J ; 33(3): 840-847, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38944730

RESUMO

Multiple myeloma (MM), mature B-cell lineage neoplasm, is characterized by abnormal clonal proliferation of plasma cells and presence of monoclonal protein (M protein). The study was conducted to reveal presenting features, laboratory findings, Eastern Cooperative Oncology Group (ECOG) performance status and skeletal survey on patients with multiple myeloma. This descriptive, cross-sectional study was carried out in the Department of Haematology, Dhaka Medical College Hospital, Dhaka, Bangladesh from January 2019 to July 2020 with a sample size of 81. Data were collected in a case record form after obtaining informed verbal consent from patients and /or their legal guardians. Relevant ethical issues and data quality assurance were taken into consideration. Data were analyzed with SPSS, Version 25.0 with presentation in figures and tables with frequency, percentage, mean and standard deviation based on data nature. Statistical tests were carried out as appropriate with 5.0% level of significance for assessing statistical association. Mean age of the patients was 58.9±12.0 years. Male female ratio was 2:1. 35(43.2%) patients were smokers with only 2(2.5%) had family history of haematological malignancies. Bone pain (72.8%) was the most common presenting feature, while hypertension (59.1%), diabetes mellitus (29.5%), respiratory illness (11.3%) and cardiac disease (11.4%) were the common co-morbidities. Most common ECOG performance status was ECOG-1(48.1%). Mean haemoglobin (Hb) was 9.4±2.3gm/dl and mean erythrocyte sedimentation rate (ESR) was 89.5±42.1 mm in 1st hour. Mean serum creatinine level was 2.0±1.85 mg/dl and ≥2.0mg/dl in 42(34.2%). Among 50 documentation serum lactate dehydrogenase (LDH) was raised in 18(36.0%). Mean serum calcium level was 9.6±1.8mg/dl >11.0mg/dL in 10(14.5%) cases. Serum albumin <3.5gm/dl in 37(49.3%), ß2-microglobulin >5.5mg/dl in 37(57.8%) cases, International staging system (ISS) stage III was in 59.4% and Bence Jones Protein (BJP) was present in 46.7% cases. Lytic lesions were present in 75.0%, In 38(74.5%) patients vertebrae were involved, while in 18(35.2%) ribs were involved, in 14(27.5%) patients skull was involved and in 3(5.9%) patients involved bones were femur, humerus, sternum and scapula. Mean plasma cells percentage was 62.1±24.9%. Immuno-Fixation Electrophoresis (IFE) revealed IgG (72.7%), IgA (18.2%), Free light chain (FLC) (9.1%). FLC ratio was ≥100 in 29.0% cases. Significant statistical association was observed between serum creatinine with Hb concentration (p<0.05), serum creatinine level with ISS staging (p<0.05) and serum calcium level (p<0/05), while insignificant association was revealed between BJP present status and serum creatinine level (p>0.05). Bone pain, fatigue, fever and neurological impairment were the common presenting features. Anaemia, renal impairment and skeletal lytic events were the prominent physical findings. ISS staging was statistically associated with serum creatinine level, while serum calcium level was associated with serum creatinine and lytic lesions.


Assuntos
Mieloma Múltiplo , Centros de Atenção Terciária , Humanos , Mieloma Múltiplo/complicações , Mieloma Múltiplo/sangue , Mieloma Múltiplo/patologia , Mieloma Múltiplo/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Transversais , Idoso , Bangladesh/epidemiologia , Adulto
3.
Mymensingh Med J ; 31(4): 954-962, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36189538

RESUMO

Though cervical cancer is a preventable disease it is the most progressive and devastating diseases posing a threat of mortality for women of developing countries. Majority of the cases present to hospital at advanced stage when treatment is less feasible. Objective is to determine the factors associated with the advanced stage presentation to the hospital, socio-demographic factor, patterns of complications and histological types among patients with carcinoma cervix. This was an observational descriptive type of cross-sectional study carried out in the department of Obstetrics and Gynecology, Mymensingh Medical College Hospital, Mymensingh, Bangladesh from 15 January to 27 September 2017. Women who were newly confirmed to have cervical cancer by histology were enrolled. Stages IIB and above was considered as advanced disease. The patients were interviewed face to face by the researcher for the purpose of collection of data. Then the patients were examined by the researcher for certain sings and those would be recorded in the check-list. Histopathological report was noted in data collection sheet. In this study data analysis was done by SPSS version 22.0. Total 66 clinically and histologically confirmed advanced ca-cervixes were taken up during this study. Most common stage was stage III, 49(74.2%) out of 66 population. Majority of female were found 34(51.5%) in age group 51-60. More than half of population 54(81.8%) were living with their husband and 12(18.1%) were widow at the time of study. High level of illiteracy among women and their problematic health seeking behavior for gynecological symptoms are responsible for advanced diagnosis of cervical cancer.


Assuntos
Neoplasias do Colo do Útero , Bangladesh/epidemiologia , Colo do Útero , Estudos Transversais , Demografia , Feminino , Hospitais , Humanos , Gravidez , Neoplasias do Colo do Útero/diagnóstico
4.
Ann R Coll Surg Engl ; 104(7): e211-e215, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35446698

RESUMO

A new variant of coronavirus (2019-nCoV) causing acute respiratory distress in humans was identified for the first time in 2019, in Wuhan, China. One of the many complications of infection with this coronavirus is hypercoagulopathy, resulting in acute thrombosis; often leading to acute limb ischaemia. Herein, we report 20 cases of COVID-19 with peripheral arterial thrombosis involving either upper or lower limbs. Some patients underwent vascular procedures and most had to undergo amputation at some level. All the cases (n=20) were referred to us during the 8-month period June 2020 to March 2021. The most common age group was between 51 and 60 years, of whom 80% were males; all the patients had diabetes. The right lower limb was most affected (50%); 15 patients underwent embolectomy. Twenty-five per cent of patients presented with wet gangrene. One patient with upper limb thrombosis recovered after embolectomy and did not require any amputation. Eighty-five per cent of patients underwent some form of amputation and the mortality rate was 10%. Arterial thrombosis is one complication patients may develop during COVID-19 illness, which may affect the outcome. Patients with comorbid conditions like diabetes are at higher risk of developing arterial thrombosis during COVID-19 infection. Susceptibility to coagulopathy may continue even after patient discharge and it is important that both patients and treating physicians are aware of this limb-threatening complication and seek early medical attention.


Assuntos
Arteriopatias Oclusivas , COVID-19 , Doenças Vasculares Periféricas , Trombose , Amputação Cirúrgica , Arteriopatias Oclusivas/complicações , COVID-19/complicações , Feminino , Humanos , Isquemia/complicações , Isquemia/cirurgia , Masculino , Pessoa de Meia-Idade , Trombose/etiologia , Trombose/cirurgia , Resultado do Tratamento
5.
Chem Commun (Camb) ; 56(24): 3543-3546, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32104853

RESUMO

An enantioconvergent method for the alkylation of o-disubstituted aryl ketones with racemic secondary alcohols is described. This process is mediated by a commercially available iridium catalyst and proceeds via hydrogen borrowing catalysis. The highly enantioenriched ß-substituted ketone products were readily cleaved to a wide range of functional groups via retro-Friedel-Crafts acylation.

6.
J Minim Access Surg ; 16(3): 224-228, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31031327

RESUMO

INTRODUCTION: Laparoscopic repair is now the treatment of choice for most cases of ventral/incisional hernia. Although the technique has undergone many refinements, there is no standard technique for difficult or complicated hernias. AIM: The aim of this study was to show the different innovative methods used to treat difficult ventral hernia through hybrid techniques. MATERIALS AND METHODS: A total of 75 (n = 75) patients underwent Laparoscopic Ventral Hernia Hybrid Mesh Repair (LVHHMR) by our surgical unit between January 2014 and December 2016. Three different techniques of repairing the defects were used. Mesh fixation time, post-operative pain score (visual analogue score) and follow-up for pain and recurrence (at 6 months, 12 months and 24 months) were recorded and analysed. RESULTS: Out of 75 patients (20 men and 55 women), the median age was 45 years and body mass index of the patients was 25-35. Types of hernias operated were paraumbilical hernias, incisional and recurrent hernias. The techniques used were (1) laparoscopic adhesiolysis, open sac excision with closure of defect and laparoscopic mesh placement, (2) laparoscopic adhesiolysis, omphalectomy with closure of defect and laparoscopic mesh placement and (3) open adhesiolysis, sac excision with closure of defect and laparoscopic mesh placement. Five patients required analgesics for 48 h. No patients complained of pain at follow-ups (1 month, 6 months, 12 months and 24 months). Mean hospital stay postoperatively was 2-3 days. CONCLUSION: LVHHMR is safe and feasible approach for complicated/difficult ventral hernias. However, further larger studies are required to establish these methods as gold standard.

8.
Angew Chem Int Ed Engl ; 58(36): 12558-12562, 2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31265208

RESUMO

Hydrogen borrowing catalysis serves as a powerful alternative to enolate alkylation, enabling the direct coupling of ketones with unactivated alcohols. However, to date, methods that enable control over the absolute stereochemical outcome of such a process have remained elusive. Here we report a catalytic asymmetric method for the synthesis of enantioenriched cyclohexanes from 1,5-diols via hydrogen borrowing catalysis. This reaction is mediated by the addition of a chiral iridium(I) complex, which is able to impart high levels of enantioselectivity upon the process. A series of enantioenriched cyclohexanes have been prepared and the mode of enantioinduction has been probed by a combination of experimental and DFT studies.

9.
J Am Chem Soc ; 140(38): 11916-11920, 2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30212192

RESUMO

An iridium catalyzed method for the synthesis of functionalized cyclohexanes from methyl ketones and 1,5-diols is described. This process operates by two sequential hydrogen borrowing reactions, providing direct access to multisubstituted cyclic products with high levels of stereocontrol. This methodology represents a novel (5 + 1) strategy for the stereoselective construction of the cyclohexane core.

10.
Angew Chem Int Ed Engl ; 56(47): 14883-14887, 2017 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-28926175

RESUMO

Catalytic oxidative cyclisation reactions have been employed for the synthesis of the E and F rings of the complex natural product target pectenotoxin 4. The choice of metal catalyst (cobalt- or osmium-based) allowed for the formation of THF rings with either trans or cis stereoselectivity. Fragment union using a modified Julia reaction then enabled the synthesis of an advanced synthetic intermediate containing the EF and G rings of the target.

11.
J Am Chem Soc ; 139(7): 2577-2580, 2017 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-28177613

RESUMO

A hydrogen borrowing reaction employing secondary alcohols and Ph* (Me5C6) ketones to give ß-branched carbonyl products is described (21 examples). This new C-C bond forming process requires low loadings of [Cp*IrCl2]2, relatively low temperatures, and up to 2.0 equiv of the secondary alcohol. Substrate-induced diastereoselectivity was observed, and this represents the first example of a diastereoselective enolate hydrogen borrowing alkylation. By utilizing the Ph* group, the ß-branched products could be straightforwardly cleaved to the corresponding esters or amides using a retro-Friedel-Crafts reaction. Finally, this protocol was applied to the synthesis of fragrance compound (±)-3-methyl-5-phenylpentanol.

12.
Iran J Vet Res ; 17(4): 231-236, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28224005

RESUMO

Current research highlights the Hspb1 based screening of eight cat populations of the world to investigate the association of newly found locus within cat mammary tumors. Total 180 cats were screened on the basis of Hspb1 4 bp deletion locus (1514-1517del4) which was observed in six mammary tumor cases in Siamese cat breed. Case-control association study revealed the non-significance with P=0.201 and an overall mutant allele frequency of 0.30 ranging from 0.20-0.40 was observed in other cat populations. Similarly, HWE was also obeyed in combined population samples with P=0.860 and found non-significant with range of 0.429-0.708 in other non-Pakistani cat populations as well. These results might be helpful to understand the association of this novel locus in a better way with large sample size of cases and may also serve as a potential marker for mammary tumor diagnosis, particularly in cats and generally in all other animal populations in comparative genetics and genomics context.

13.
J Am Chem Soc ; 137(50): 15664-7, 2015 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-26654947

RESUMO

The application of an iridium-catalyzed hydrogen borrowing process to enable the formation of α-branched ketones with higher alcohols is described. In order to facilitate this reaction, ortho-disubstituted phenyl and cyclopropyl ketones were recognized as crucial structural motifs for C-C bond formation. Having optimized the key catalysis step, the ortho-disubstituted phenyl products could be further manipulated by a retro-Friedel-Crafts acylation reaction to produce synthetically useful carboxylic acid derivatives. In contrast, the cyclopropyl ketones underwent homoconjugate addition with several nucleophiles to provide further functionalized branched ketone products.

14.
J Minim Access Surg ; 7(1): 68-70, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21197246

RESUMO

Laparoscopic splenectomy is now the gold standard for patients with idiopathic thrombocytopenic purpura (ITP) undergoing splenectomy. There are a few reports in literature on single-incision laparoscopic (SIL) splenectomy. Herein, we describe a patient undergoing SIL splenectomy for ITP without the use of a disposable port device. We report a 20-year-old female patient with steroid-refractory ITP having a platelet count of 14,000/cmm who underwent a SIL splenectomy. Dissection was facilitated by the use of a single articulating grasper and a gastric traction suture and splenic vessels were secured at the hilum with an endo-GIA stapler. She made an uneventful postoperative recovery and was discharged on the second postoperative day. She is doing well with no visible scar at 8-month follow-up.

15.
Curr Med Res Opin ; 26(8): 1873-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20528107

RESUMO

BACKGROUND/AIM: People of south Asian origin have an excessive risk of morbidity and mortality from cardiovascular disease. We examined the effect of ethnicity on known risk factors and analysed the risk of cardiovascular events and mortality in UK south Asian and white Europeans patients with type 2 diabetes over a 2 year period. METHODS: A total of 1486 south Asian (SA) and 492 white European (WE) subjects with type 2 diabetes were recruited from 25 general practices in Coventry and Birmingham, UK. Baseline data included clinical history, anthropometry and measurements of traditional risk factors - blood pressure, total cholesterol, HbA1c. Multiple linear regression models were used to examine ethnicity differences in individual risk factors. Ten-year cardiovascular risk was estimated using the Framingham and UKPDS equations. All subjects were followed up for 2 years. Cardiovascular events (CVD) and mortality between the two groups were compared. TRIAL REGISTRATION NUMBER: ISRCTN 38297969. FINDINGS: Significant differences were noted in risk profiles between both groups. After adjustment for clustering and confounding a significant ethnicity effect remained only for higher HbA1c (0.50 [0.22 to 0.77]; P = 0.0004) and lower HDL (-0.09 [-0.17 to -0.01]; P = 0.0266). Baseline CVD history was predictive of CVD events during follow-up for SA (P < 0.0001) but not WE (P = 0.189). Mean age at death was 66.8 (11.8) for SA vs. 74.2 (12.1) for WE, a difference of 7.4 years (95% CI 1.0 to 13.7 years), P = 0.023. The adjusted odds ratio of CVD event or death from CVD was greater but not significantly so in SA than in WE (OR 1.4 [0.9 to 2.2]). LIMITATIONS: Fewer events in both groups and short period of follow-up are key limitations. Longer follow-up is required to see if the observed differences between the ethnic groups persist. CONCLUSION: South Asian patients with type 2 diabetes in the UK have a higher cardiovascular risk and present with cardiovascular events at a significantly younger age than white Europeans. Enhanced and ethnicity specific targets and effective treatments are needed if these inequalities are to be reduced.


Assuntos
Povo Asiático/estatística & dados numéricos , Doenças Cardiovasculares/etnologia , Doenças Cardiovasculares/mortalidade , Diabetes Mellitus Tipo 2/etnologia , Diabetes Mellitus Tipo 2/mortalidade , Adulto , Distribuição por Idade , Idoso , Sudeste Asiático/etnologia , Feminino , Seguimentos , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Morbidade , Prevalência , Fatores de Risco , Distribuição por Sexo , Reino Unido/epidemiologia , População Branca/estatística & dados numéricos
16.
Leukemia ; 23(4): 746-52, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19148136

RESUMO

Glucocorticoids (GCs) induce apoptosis in lymphoid lineage cells and are therefore used in the therapy of acute lymphoblastic leukemia (ALL) and related malignancies. MicroRNAs (miRNAs) and the related mirtrons are ~22 nucleotide RNAs derived from polymerase-II transcripts and implicated in the control of essential biological functions, including apoptosis. Whether GCs regulate miRNA-encoding transcription units is unknown. We investigated miRNA/mirtron expression and GC regulation in 8 leukemia/lymphoma in vitro models and 13 ALL children undergoing systemic GC monotherapy using a combination of expression profiling techniques, real time reverse transcription (RT)-PCR and northern blotting to detect mature miRNAs and/or their precursors. We found that mature miRNA regulations can be inferred from expression data of their host genes. Although a simple miRNA-initiated canonical pathway to GC-induced apoptosis or cell cycle arrest did not emerge, we identified several miRNAs/mirtrons that were regulated by GC in patients and cell lines, including the myeloid-specific miR-223 and the apoptosis and cell cycle arrest-inducing miR15 ~ 16 clusters. In an in vitro model, overexpression of miR15b ~ 16 mimics increased and silencing by miR15b ~ 16 inhibitors decreased GC sensitivity. Thus, the observed complex changes in miRNA/mirtron expression during GC treatment might contribute to the anti-leukemic GC effects in a cell context-dependent manner.


Assuntos
Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , MicroRNAs/análise , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Apoptose , Linhagem Celular Tumoral , DNA Polimerase II/genética , Perfilação da Expressão Gênica , Glucocorticoides/uso terapêutico , Humanos , MicroRNAs/genética , RNA Mensageiro
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