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1.
Cont Lens Anterior Eye ; : 102246, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38851947

RESUMO

PURPOSE: Myopia (short-sightedness) is a growing vision problem worldwide. Currently atropine eye drops are used to control the progression of myopia but these suffer from potential lack of bioavailability and low ocular residence time. Commercially available myopia control contact lenses are also used to limit myopia progression, but neither atropine nor contact lenses individually completely stop progression. Development of myopia control contact lenses which could deliver therapeutic doses of atropine is thus desirable and may provide increased efficacy. This study was designed to explore the feasibility of attaching atropine to etafilcon A contact lenses through an esterification reaction. METHODS: Carboxylic acid groups on etafilcon A contact lenses were quantified using Toluidine Blue O. The carboxylic acid groups in etafilcon A contact lenses were activated using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC-HCl) and N-hydroxysuccinimide (NHS) crosslinkers after which atropine was added to undergo potential binding via esterification. Atropine was released from lenses by alkaline hydrolysis. Reverse phase high performance liquid chromatography (HPLC) was used to detect and quantify the released atropine and its degradation products in solution. Contact lenses that had not been activated by EDC-NHS (controls) were also examined to determine the amount of atropine that could be absorbed rather than chemically bound to lenses. RESULTS: Each etafilcon A contact lens contained 741.1 ± 5.5 µg carboxylic acid groups which may be available for esterification. HPLC had a limit of detection for atropine of 0.38 µg/mL and for tropic acid, an atropine degradation product, of 0.80 µg/mL. The limits of quantification were 1.16 µg/mL for atropine and 2.41 µg/mL for tropic acid in NH4HCO3. The etafilcon A lenses adsorbed up to 7.69 µg atropine when incubated in a 5 mg/mL atropine solution for 24 h. However, there was no evidence that atropine could be chemically linked to the lenses, as washing in a high concentration of NaCl removed all the atropine from the contact lenses with no atropine being subsequently released from the lenses after incubating in 0.01 N NH4HCO3. CONCLUSIONS: Etafilcon A contact lenses contain free carboxylic acids which may be an appropriate option for attaching drugs such as atropine. Etafilcon A lenses adsorbed up to 7.69 µg atropine, which would be more than enough to deliver atropine to eyes to control myopia. However, atropine could not be chemically bound to the carboxylic acids of the etafilcon A lenses using this methodology.

2.
Cureus ; 15(12): e50209, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38192928

RESUMO

OBJECTIVES: The aim of this study is to compare the fracture resistance and the mode of failure of endodontically treated permanent mandibular premolars restored with two types of posts: diamond posts and glass-fiber posts. MATERIALS AND METHODS: Forty human mandibular premolars indicated for orthodontic extraction were collected for this study and were similar in shape, size, and length. The teeth were sectioned horizontally, 1 mm above the cementoenamel junction. Root canal treatment was carried out on all specimens, and obturation was done by lateral condensation. The teeth were randomly divided into two groups. The post space was prepared in the first group to receive the diamond posts and in the second group to receive the fiber posts. A dual-cure resin material was used for cementing the posts and building up the cores. Then, they were subjected to a compressive load at a cross-head speed of 1 mm per minute and at an angle of 135 degrees to the long axis of the tooth until a fracture occurred using a universal testing machine. Fracture resistance and the mode of failure were assessed. The fracture above the acrylic block level was considered favorable, and the fracture below the acrylic block level was considered unfavorable. The data were analyzed statistically. The statistical analysis of fracture resistance between the two groups was carried out with a t-test. The statistical analysis for the failure mode of the teeth was carried out with a chi-square test. RESULTS: There was a statistically significant difference showing that the diamond posts had better fracture resistance when compared with glass-fiber posts, while there was no statistically significant difference in terms of the failure mode between the two posts. CONCLUSION: Within the limitations of this study, it can be concluded that diamond posts showed higher fracture resistance than glass-fiber posts. Glass-fiber posts showed more favorable failure modes but were statistically insignificant compared to diamond posts.

3.
Materials (Basel) ; 14(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34500952

RESUMO

In this research, a biopolymer-based electrolyte system involving methylcellulose (MC) as a host polymeric material and potassium iodide (KI) salt as the ionic source was prepared by solution cast technique. The electrolyte with the highest conductivity was used for device application of electrochemical double-layer capacitor (EDLC) with high specific capacitance. The electrical, structural, and electrochemical characteristics of the electrolyte systems were investigated using various techniques. According to electrochemical impedance spectroscopy (EIS), the bulk resistance (Rb) decreased from 3.3 × 105 to 8 × 102 Ω with the increase of salt concentration from 10 wt % to 40 wt % and the ionic conductivity was found to be 1.93 ×10-5 S/cm. The dielectric analysis further verified the conductivity trends. Low-frequency regions showed high dielectric constant, ε' and loss, ε″ values. The polymer-salt complexation between (MC) and (KI) was shown through a Fourier transformed infrared spectroscopy (FTIR) studies. The analysis of transference number measurement (TNM) supported ions were predominantly responsible for the transport process in the MC-KI electrolyte. The highest conducting sample was observed to be electrochemically constant as the potential was swept linearly up to 1.8 V using linear sweep voltammetry (LSV). The cyclic voltammetry (CV) profile reveals the absence of a redox peak, indicating the presence of a charge double-layer between the surface of activated carbon electrodes and electrolytes. The maximum specific capacitance, Cs value was obtained as 118.4 F/g at the sweep rate of 10 mV/s.

4.
Pak J Med Sci ; 37(5): 1371-1375, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34475914

RESUMO

OBJECTIVES: To determine the long-term outcome and complications of non-transecting anastomotic bulbar urethroplasty for the treatment of small bulbar urethral strictures presenting at Liaquat National Hospital, Karachi. METHODS: This interventional study was conducted from January 2012 to December 2019 with the study duration of eight year at Liaquat National Hospital, Karachi. All patients presenting in the outpatient department with urethral strictures were included in the study. Patients were evaluated postoperatively for complications and outcomes were determined. The data was analyzed using SPSS v.25. RESULTS: A total of 358 patients were treated with non-transecting anastomotic bulbar urethroplasty during this 8-years period. The most common site of stricture formation was bulbar urethra 186 (50%), followed by bulbo-membranous urethra; 103 (31%), and bulbo-penile urethra; 69 (19%). The mean stricture was 1.2 cm (0.5-2.5 cm) in length. The main postoperative complications were scrotal swelling in 7 (1.9%), wound infection in 6 (1.6%), wound dehiscence in 3 (0.8%), and transient sexual dysfunction in 31 (8.6%) patients with an overall initial success rate of 97.8%. No permanent deficit in sexual function was reported. CONCLUSIONS: Non-transecting anastomotic bulbar urethroplasty has a good outcome with insignificant postoperative complications in patients with small bulbar urethral stricture disease.

5.
Pan Afr Med J ; 39: 20, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34394811

RESUMO

INTRODUCTION: incidental prostate cancer findings reflect the great burden of prostatic cancer across the globe. Our 10 year retrospective analysis aimed to identify the incidence and clinic-pathologic features of prostate cancer incidentally detected in patients undergoing transurethral resection of the prostate (TURP) for benign prostatic hyperplasia (BPH), and to estimate the clinical value of pathologic review of all TURP specimens. METHODS: after excluding patients with a known diagnosis of prostate cancer prior to TURP a total of 2,386 men (ages 25-98) were identified by pathology (TURP) specimens. Yearly incidences, Gleason score, grade, pathologic stage were recorded for all incidental prostate cancer patients. RESULTS: a total of 256 (10.7%) patients were found to have prostate cancer. Mean Age was 68.51±9.22 years. T1a and T1b stage prostatic carcinoma was found in 9.9% and 90.1% of these patients respectively. Forty-nine percent (49%) patients had higher Gleason scores (>7). After subtracting average incidences between 5-year intervals, a statistical rise of almost 4% was found. CONCLUSION: our analysis concludes that a large proportion (10.7%) of patients had incidental prostate cancer and the incidence was increasing in recent years in Pakistan and in comparison, to Asian countries. In Pakistan there is a scarcity of updated national cancer registries. The growing incidence of high Gleason scores requires keen and prompt attention. The diverse ethnic and socioeconomic background of patients propels their propensity towards loss of follow up with already limited tertiary healthcare institutes in Pakistan. This pathologic review of TURP specimens is valuable for Asiatic and non-Asiatic populations.


Assuntos
Hiperplasia Prostática/cirurgia , Neoplasias da Próstata/diagnóstico , Ressecção Transuretral da Próstata , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Incidência , Achados Incidentais , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Paquistão , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Centros de Atenção Terciária
6.
Materials (Basel) ; 15(1)2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-35009315

RESUMO

The polymer electrolyte system of methylcellulose (MC) doped with various sodium bromide (NaBr) salt concentrations is prepared in this study using the solution cast technique. FTIR and XRD were used to identify the structural changes in solid films. Sharp crystalline peaks appeared at the XRD pattern at 40 and 50 wt.% of NaBr salt. The electrical impedance spectroscopy (EIS) study illustrates that the loading of NaBr increases the electrolyte conductivity at room temperature. The DC conductivity of 6.71 × 10-6 S/cm is obtained for the highest conducting electrolyte. The EIS data are fitted with the electrical equivalent circuit (EEC) to determine the impedance parameters of each film. The EEC modeling helps determine the circuit elements, which is decisive from the engineering perspective. The DC conductivity tendency is further established by dielectric analysis. The EIS spectra analysis shows a decrease in bulk resistance, demonstrating free ion carriers and conductivity boost. The dielectric property and relaxation time confirmed the non-Debye behavior of the electrolyte system. An incomplete semicircle further confirms this behavior model in the Argand plot. The distribution of relaxation times is related to the presence of conducting ions in an amorphous structure. Dielectric properties are improved with the addition of NaBr salt. A high value of a dielectric constant is seen at the low frequency region.

7.
Polymers (Basel) ; 12(10)2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33019543

RESUMO

Compatible green polymer electrolytes based on methyl cellulose (MC) were prepared for energy storage electrochemical double-layer capacitor (EDLC) application. X-ray diffraction (XRD) was conducted for structural investigation. The reduction in the intensity of crystalline peaks of MC upon the addition of sodium iodide (NaI) salt discloses the growth of the amorphous area in solid polymer electrolytes (SPEs). Impedance plots show that the uppermost conducting electrolyte had a smaller bulk resistance. The highest attained direct current DC conductivity was 3.01 × 10-3 S/cm for the sample integrated with 50 wt.% of NaI. The dielectric analysis suggests that samples in this study showed non-Debye behavior. The electron transference number was found to be lower than the ion transference number, thus it can be concluded that ions are the primary charge carriers in the MC-NaI system. The addition of a relatively high concentration of salt into the MC matrix changed the ion transfer number from 0.75 to 0.93. From linear sweep voltammetry (LSV), the green polymer electrolyte in this work was actually stable up to 1.7 V. The consequence of the cyclic voltammetry (CV) plot suggests that the nature of charge storage at the electrode-electrolyte interfaces is a non-Faradaic process and specific capacitance is subjective by scan rates. The relatively high capacitance of 94.7 F/g at a sweep rate of 10 mV/s was achieved for EDLC assembly containing a MC-NaI system.

8.
J Ayub Med Coll Abbottabad ; 32(1): 99-103, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32468766

RESUMO

BACKGROUND: Urethral stricture disease has significant economic impact throughout world. The bulbar urethra is the commonest site for urethral strictures (Approx 50%) followed by penile urethra in most of the published literature. In developing countries trauma (road traffic accident and iatrogenic) is the leading cause of urethral stricture disease. Younger patients have usually idiopathic type as compare to old age group, which present more frequently with iatrogenic and trauma related urethral strictures. METHODS: This Qausi Experimental study was conducted from May2012-June2016 of duration at Liaquat National Hospital Karachi. All the patients diagnosed with short urethral strictures related to bulbar urethra were included in this study. All the patients underwent non transecting bulbar urethroplasty. All patients were assessed preoperatively, peri-operatively and postoperatively and on follow-up visits as; on 2nd, 8th and 24th week. All the data regarding outcome was recorded on the Performa and analyzed on SPSS V20. RESULTS: Total of 179patients were included, mean age was 38±SD15.3years (range 20- 65years). Anatomically bulbar urethra was affected in 52% of the cases followed by bulbopenile, bulbomembranous region. Etiologically idiopathic type was found in 40% cases, while trauma 21%, iatrogenic injury 26% and UTI 13% were also reasons. Stricture length was mean1.1±SD 1.4 cm (range 0.5-2.5cm). Preoperative Uroflowmetry revealed mean Qmax of 10.5±SD 5.3 ml/sec. Mean operative time was 35±SD 4.6 minutes, 7 patients had conversion to other procedures (3.91%), Postoperative complications were minimal. Mean follow up was 12±SD 21 months (range 6 months to 3 years). On initial follow up at 8th week and 24th week, Qmax was significantly improved. Only 3 patients required DVIU after the 24th week. Initial success rate after 24th week was 98.3% and eventually 100% at the long-term follow-up. CONCLUSIONS: non-transecting anastomotic bulbar urethroplasty (NTABU) is a new standard of care for the short bulbar urethral stricture up to 2.5cm. Idiopathic aetiology, iatrogenic and posttraumatic urethral strictures in selective patients can safely be operated with this technique.


Assuntos
Procedimentos de Cirurgia Plástica/métodos , Uretra/cirurgia , Estreitamento Uretral/cirurgia , Procedimentos Cirúrgicos Urológicos Masculinos/métodos , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão , Procedimentos de Cirurgia Plástica/efeitos adversos , Procedimentos de Cirurgia Plástica/estatística & dados numéricos , Procedimentos Cirúrgicos Urológicos Masculinos/efeitos adversos , Procedimentos Cirúrgicos Urológicos Masculinos/estatística & dados numéricos , Adulto Jovem
9.
J Ayub Med Coll Abbottabad ; 31(3): 331-335, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31535500

RESUMO

BACKGROUND: Urinary incontinence is an uncommon problem in males but has major impact on daily living. This study aimed to highlight the outcome of surgical treatment in terms of safety, efficacy and cost-effectiveness in the management of urinary incontinence.. METHODS: A Total of 48 patients, prospective experimental study, in the duration of 4 years conducted at Department of Urology, Liaquat National Hospital & Medical College. Patients having moderate to severe urinary incontinence for 1 year after transurethral resection of prostate, radical prostatectomy, road traffic accident with pelvic fracture causing neurologic damage were included in this study. Patients having mild incontinence, having multiple co-morbid conditions were excluded from this study. Outcome of surgery was noted during follow up visit after 13 month (median). The data was obtained and analysed by using SPSS version 20. Mean and standard deviation for quantitative data, frequency and percentage for categorical variables were presented. RESULTS: Out of 48 patients having urinary incontinence, 28 (58.3%) had severe urinary incontinence while 20 (41.7%) had moderate incontinence. After surgery, 28 (58.3%) patient had no leakage all day, 12 (25%) had some leakage while bending and 8 (16.7%) had no improvement in symptoms. On ultrasound recorded after voiding in post-surgery patients, 40 (83.3%) had no residual found in bladder while 8(16.7%) could not be assessed due to persistence of urinary incontinence. CONCLUSIONS: Our study predicted that in patients having moderate to severe urinary incontinence, Prolene Mesh repair anchoring with Prolene suture can be an efficient and costeffective treatment for the urinary incontinence with least complications.


Assuntos
Polipropilenos/uso terapêutico , Complicações Pós-Operatórias , Telas Cirúrgicas , Incontinência Urinária , Humanos , Masculino , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Estudos Prospectivos , Prostatectomia/efeitos adversos , Suturas , Centros de Atenção Terciária , Incontinência Urinária/epidemiologia , Incontinência Urinária/etiologia , Incontinência Urinária/cirurgia
10.
J Pak Med Assoc ; 65(9): 954-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26338740

RESUMO

OBJECTIVE: To evaluate various prognostic factors which determine outcome after surgical repair of vesicovaginal fistula. METHODS: The retrospective study was conducted at Koohi Goth Fistula Hospital, Karachi, and comprised data related to patients having undergone vesicovaginal fistula repair from January 2007 to June 2012. Multivariate analysis of the record was done using SPSS 19 software determining odds ratio with 95% confidence interval. RESULTS: Record of 640 patients were analysed with an overall success in 558(87.2%) cases. Multivariate analysis determined that the recurrence of vesicovaginal fistula was significantly related to multiplicity (9-fold recurrence risk), pre-operative size (10-fold recurrence risk for fistula >2cm compared to <1cm), secondary repair (5-fold risk) and duration of the fistula (3-fold risk).Interposition of flap and delayed reconstruction (between 6 weeks and 1 year) was related to successful surgical outcome. Age, parity, aetiology, route of repair and location of fistula were not significant (p>0.05 each) prognostic factors for recurrence. CONCLUSIONS: Successful surgical repair of vesicovaginal fistula require careful evaluation of various factors, including number, size, previous attempts to surgical repair and duration of fistula.


Assuntos
Fístula Vesicovaginal/cirurgia , Adolescente , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Paquistão , Prognóstico , Recidiva , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
11.
J Coll Physicians Surg Pak ; 25(1): 71-2, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25604374

RESUMO

Ovarian dermoid cyst is one of the common problems seen in gynaecology, they make upto 10 - 25% of all ovarian neoplasms and are usually seen in younger age group. Mature cystic teratomas are usually an incidental finding during a clinical examinations, radiographic studies or during abdominal operations performed for other indications. Other presentations include abdominal symptoms from complications of the cyst such as torsion, rupture, infection and malignant transformation. Dermoid cyst in urinary bladder is a very rare condition. Here we are presenting a case report of a female who presented with lower abdominal pain and passage of hair in urine (pilimiction). Upon investigations it was found that patient had right sided dermoid which had penetrated the wall of bladder and expelled its contents in the bladder. This was a very rare presentation and no such case has been reported in Pakistani literature.


Assuntos
Dor Abdominal/etiologia , Cisto Dermoide/patologia , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/patologia , Teratoma/complicações , Bexiga Urinária/patologia , Adulto , Cisto Dermoide/cirurgia , Feminino , Humanos , Neoplasias Embrionárias de Células Germinativas/cirurgia , Neoplasias Ovarianas/cirurgia , Teratoma/cirurgia , Resultado do Tratamento , Bexiga Urinária/cirurgia
12.
J Pak Med Assoc ; 62(5): 448-53, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22755307

RESUMO

OBJECTIVE: To analyse the result of intra-cytoplasmic sperm injection (ICSI) by using surgically retrieved sperms in the azoospermic male. METHODS: Eight (9 cycles) azoospermic men were given the intra-cytoplasmic sperum injection after sperms were collected through surgical retrieval either by percutaneous epididymal sperm aspiration (PESA) or testicular sperm extraction (TESE) at the Sindh Institute of Reproductive Medicine (SIRM), Karachi, which is an assisted reproductive technology centre. Fertilisation, cleavage and pregnancy rates were calculated in their spouses with surgical sperm collection (SSC) and intra-cytoplasmic sperm injection. The study related to the period between September 2007 and February 2009. Statistical analysis were done using SPSS version 11.0. RESULT: After the intra-cytoplasmic sperm injection procedure, fertilisation rate of 72.72% and cleavage rate of 78.12% were achieved in the eight patients. A total of 3 (33.33%) clinical pregnancies were obtained through the transfer of embryo from surgical sperm collection in the azoospermic men. CONCLUSION: Intra-cytoplasmic sperm injection with surgical sperm collection proved to be the only successful treatment for men with azoospermia. It gave 33.33% chances of fatherhood in men who were previously labelled infertile. Results were found to be promising and are expected to improve with time and experience.


Assuntos
Azoospermia/terapia , Taxa de Gravidez , Injeções de Esperma Intracitoplásmicas , Adulto , Feminino , Humanos , Masculino , Paquistão , Gravidez , Estudos Prospectivos , Recuperação Espermática
13.
J Pak Med Assoc ; 62(8): 781-4, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23862249

RESUMO

OBJECTIVE: To compare the stone clearance of upper with middle and lower ureteric stones by using ureteroscopic pneumatic lithotripsy. METHODS: The study was conducted in the Department of Urology, Liaquat National Hospital, Karachi, from February 2009 to February 2010. A total of 90 patients were selected and divided into three groups of 30, each according to the location of stone in the ureter. All patients underwent ureteroscopic pneumatic lithotripsy with 8.5 Fr Wolf rigid ureteroscope and Wolf 2mm probe used for stone fragmentation. All patients were evaluated with X-ray KUB, ultrasound KUB and IVU. Follow-up studies included X-ray and ultrasound KUB performed on 1st postoperative day, after 1 week and at the end of 2nd week. Presence of stone after last follow-up was considered as failure of the procedure. RESULTS: Total number of patients were 90 and mean age was 27.47 +/- 5.8 years. Male female ratio was 2.1:1. Mean stone size was 11.44 +/- 1.41mm. According to the location of the stones, the success rate of pneumatic lithotripsy for upper, middle, and lower ureteral stones was 86.7%, 93.3%, and 96.7% respectively. Completely fragmented stones cleared spontaneously within two weeks in 83 of 90 cases so the overall stone-free rate was 92.2%. CONCLUSION: Ureteroscopic Pneumatic Lithotripsy is an acceptable form of treatment for upper ureteric calculi in addition to middle and lower ureteric calculi. It is a simple, reliable, effective, rapid and safe procedure.


Assuntos
Litotripsia/métodos , Cálculos Ureterais/terapia , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Masculino , Estudos Retrospectivos , Resultado do Tratamento , Cálculos Ureterais/diagnóstico , Ureteroscopia , Adulto Jovem
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