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1.
Res Sq ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38659840

RESUMO

Objectives: Post-discharge patient-reported outcomes from trauma registries can be used to measure trauma care quality. However, studies reflecting the Asian experience are limited. Therefore, we aim to develop a digital trauma registry to prospectively capture patient-reported outcomes (PROs) at one-, three-, six-, and twelve-months post-injury in Pakistan. Methods: We will use a cohort study design to develop a digital trauma registry at two tertiary care facilities (Aga Khan University Hospital & Jinnah Postgraduate Medical Center) in Karachi, Pakistan. The registry will include all admitted adult trauma patients (≥18 years). Data collection will be digital using tablets, with mortality, level of disability, and functional status, quality of life being the outcomes. Telephonic interviews will be conducted with the patients and caregivers for follow-up data collection. Discussion: The high disability burden following accidental trauma imposes a significant burden and cost on individuals and society. Therefore, the trauma registry would fill this gap by capturing post-discharge long-term PROs. It will provide the injured patient's post-discharge situation, challenges, and future directions for incorporating long-term PROs in low-resource settings. Including long-term measures in routine follow-ups will provide insights into physical, social, and policy barriers and help advance injury care research.

2.
J Neurosci Rural Pract ; 14(4): 610-614, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38059256

RESUMO

Objective: To determine the diagnostic accuracy of the SLR test in elderly patients suffering from lumbar disk herniation with sciatica and low back pain, using magnetic resonance imaging (MRI) as the gold standard. Materials and Methods: A cross-sectional study was conducted at Jinnah Postgraduate Medical Center and a total of 120 patients, above 60 years of age, with symptomatic lumbar disk herniation were enrolled. SLR test was performed and the results recorded. MRI of the lumbar spine was undertaken for confirmation of disk herniation. Results: The sensitivity of the SLR test in patients 60 years and older is 33.3%. A decrease in the diagnostic accuracy of the SLR test with an increment in age was also noted. Conclusion: It was found that with an increment in age, there is a steady decline in the diagnostic accuracy of SLR Test.

3.
Small ; 18(31): e2202626, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35802900

RESUMO

Binary van der Waals heterostructures of graphene (Gr) and transition metal dichalcogenide (TMDC) have evolved as a promising candidate for photodetection with very high responsivity due to the separation of photo-excited electron-hole pairs across the interface. The spectral range of optoelectronic response in such hybrids has so far been limited by the optical bandgap of the light absorbing TMDC layer. Here, the bidirectionality of interlayer charge transfer is utilized for detecting sub-band gap photons in Gr-TMDC heterostructures. A Gr/MoSe2 heterostructure sequentially driven by visible and near infra-red (NIR) photons is employed, to demonstrate that NIR induced back transfer of charge allows fast and repeatable detection of the low energy photons (less than the optical band gap of the TMDC layer). This mechanism provides photoresponsivity as high as ≈3000 A W-1 close to the communication wavelength. The experiment provides a new strategy for achieving highly efficient photodetection over a broad range of energies beyond the spectral bandgap with the 2D semiconductor family.

4.
Cureus ; 14(4): e24125, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35573500

RESUMO

BACKGROUND: In contrast to other breast surgeries, modified radical mastectomy (MRM) with axillary lymph node clearance involves intense tissue dissection, with postoperative seroma formation and pain being the major complaints affecting patients. Among these, 40% of females experience acute postoperative pain, and between 25 to 60% develop persistent chronic postsurgical pain. The rationale of this study was that minimally invasive procedures can result in immediate pain relief in patients undergoing mastectomy, which has been proven to satisfy their needs and lead to early discharge in the local population. OBJECTIVE: This study determined to find out the efficacy of instilling bupivacaine on wounds by means of surgical drains in controlling pain after MRM. METHODOLOGY: This was a randomized control study trial that was carried out in Surgical Unit 1, Ward 3, Jinnah Postgraduate Medical Centre, Karachi, from November 2020 to April 2021. All patients tested negative for coronavirus disease 2019 (COVID-19) by PCR test before randomly allocating them into two groups. Thirty women in Group B received 40 ml of 0.25% injection bupivacaine, and 30 in Group C received no drug. Duration of analgesia was recorded as time in hours when the patient was received after surgery in the post-anesthesia care unit until the patient felt ache and discomfort of > three scores according to the visual analog pain score chart (VAS). RESULTS: The average age was 52.48±4.76 years. The mean period of time during which analgesia was observed was significantly higher in Group B as compared to Group C (10.93±1.84 vs 5.03±1.35 hours, p=0.0005). CONCLUSION: There is improvement in postoperative analgesia after instilling bupivacaine through surgical drains on wound beds in MRM patients.

5.
Cureus ; 14(4): e23773, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35530833

RESUMO

Background Chronic cholecystitis is inflammation of the gall bladder usually caused by stones. The aim was to find out the prevalence of mucocele and empyema in chronic cholecystitis using cholecystectomy findings and histopathological reports. Methodology This was a cross-sectional observational study conducted in Surgical Ward 1, Jinnah Postgraduate Medical Center, Karachi from December 2019 to December 2021 for two years. Patients above 12 years of age diagnosed with chronic cholecystitis with cholelithiasis on clinical examination and investigations were included. Patients who were diagnosed with acute cholecystitis, mucocele, or empyema on clinical examination and ultrasonography were excluded from the study. Laparoscopic cholecystectomy was done and operative findings were noted. Gall bladder specimens were examined for mucocele and empyema and were sent for histopathology. Results were recorded and analyzed. Results There were 241 patients diagnosed with chronic cholecystitis with cholelithiasis on clinical examination and investigations. On examination, tenderness in the right hypochondrium was absent in all patients. Chronic cholecystitis was proved on histopathology in 231 patients (95.85%). Other findings diagnosed on peroperative findings and histopathology reports were strawberry gall bladder (2.41%), empyema (0.83%), mucocele (0.41%), and polyp (0.41%). Two hundred eight patients were female (86.31%), 33 were male(13.69%). The male to female ratio was 1:6.43. The average age was 31 years. Conclusion Inflammation and fibrosis of the gallbladder around Calot's triangle increase the chances of vascular and common bile duct injury. In such cases, cholecystectomy can become difficult. It was concluded that empyema, mucocele, and strawberry gall bladder could be found in chronic cholecystitis, and cholecystectomy becomes difficult in such cases.

6.
Cureus ; 14(3): e23683, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35505755

RESUMO

Introduction The aim of this study was to compare epidemiological characteristics of breast cancer in young adolescent women (YAW) versus older women (OW). Methods This was a cross-sectional prospective observational study, conducted in Ward 3, Jinnah Postgraduate Medical Center, Karachi, Pakistan, from September 2021 to February 2022. A total of 120 female patients were recruited in this study from the Outpatient Department of Jinnah Postgraduate Medical Center, out of which 22 patients were below the age of 40 years and 98 were above 40 years. For breast cancer diagnosis, we used the triple assessment method involving clinical examination, radiology, and histopathology. Diagnosed patients were further evaluated for hormonal status and metastatic workup. Results were noted on a performa, and differences between both age groups were analyzed. Results Out of 120 patients, 22 were younger than 40 years and 98 were older than 40 years. YAW used to present late after the appearance of symptoms. Patients of both age groups mostly presented with breast lumps (68.18% in YAW and 81.6% in OW). YAW presented with larger sizes of lumps and with more nodal involvement as compared to OW. BI-RADS IV (Breast Imaging Reporting and Data System Category IV) was the most commonly observed (27.27% in YAW and 48.97% in OW) mammographic finding in both age groups. Invasive ductal carcinoma was the most common histological type in both age groups (72.73% in YAW and 76.53% in OW). The triple-negative disease was more commonly found in YAW than OW (40.91% in YAW vs 21.43% in OW). We found that usually YAW presented at advanced stages (stages III and IV, 54.55%) and higher grades (grade III, 63.63%). Conclusion Breast cancer in young patients is rare but more aggressive with higher grades, advanced stages, and poor prognostic features. Heredity is mainly the risk factor in young breast cancer patients. There should be proper screening programs for high-risk group for early diagnosis and prompt treatment. Other age-specific concerns such as psychological impact of disease should be addressed as well.

7.
Int J Surg Protoc ; 25(1): 66-70, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-34013147

RESUMO

INTRODUCTION: This two-phase study seeks to contribute to research in the field of rural cancer health; specifically, the aim is to gain insight into the experiences of seeking, accessing and using information and health services throughout the cancer journey (diagnosis, treatment and follow-up care) for recently diagnosed (≤6 months) older patients (≥65 years) in rural areas. METHODS AND ANALYSIS: Data will be collected through in-depth semi-structured interviews. In phase 1 (before 23rd March 2020) interviews were conducted with healthcare professionals (HCP) to explore their experiences of delivering care to their elderly patients. In the second phase (starting January 2021) we will conduct interviews with cancer patients to understand the impact of COVID-19 and shielding on their experiences of being diagnosed, attending appointments and accessing and receiving support from community organisations and informal support from family and friends. Data gathered will be analysed using the Framework Method. ETHICS: The study has been approved by the Health Research Authority and the United Lincolnshire Hospitals NHS Trust. Initial favourable ethical opinion was granted on 1st October 2019. Second favourable ethical opinion for amendments to reflect the impact of COVID-19 was received on 10th August 2020. The study protocol has been registered on Research Registry.

8.
Cureus ; 13(11): e19894, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34976505

RESUMO

Introduction Gallstones are deposits of digestive fluid that is hardened into small pellets. Gallstones can be symptomatic or asymptomatic. The present study assessed the sociodemographic and clinical characteristics of patients under the age of 30 years old with symptomatic gallstones. Methodology A prospective, observational study was conducted at Surgical Unit-3, at Jinnah Postgraduate Medical Centre (JPMC), Pakistan, from July 2020 to July 2021. All patients suspected of having gallstone disease underwent ultrasonic examination. A diagnosis of gallstone disease was made if the gallbladder showed a hyperechoic mass casting a posterior acoustic shadow, with a change of position. All of the patients with gallstone disease were hospitalized. The patients were asked about their age, past history (with special emphasis on last pregnancy and years of oral contraceptive use, if any), socioeconomic status, and other demographic data. The patients were treated with a cholecystectomy, either laparoscopic or open. Postcholecystectomy complications, if any, were recorded. Results A total of 210 patients under the age of 30 years were included. The mean age of patients was 25 ± 3 years. The majority of the population were females, i.e., 170 (81%). Upon assessing the risk factors, it was found that 31.84% of the female patients had used oral contraceptives, 32.96% were pregnant at the time of presentation, 20.48% had diabetes mellitus, and 27.14% had a history of gallstones. Furthermore, it was found that about 114 (54.29%) patients were overweight with a body mass index (BMI) of 25-30 kg/m2. High triglyceride levels and high cholesterol levels were found in 108 (51.43%) and 115 (54.76%) of the patients, respectively, indicating a link between symptomatic gallstones and younger age. Conclusion Our study indicated that young people are prone to symptomatic gallstones. The rate of disease was considerably high among females and in patients with high cholesterol and triglyceride levels and abnormal body mass index. Further exploratory studies are needed to determine the cause of gallstones.

9.
Clin Nutr ESPEN ; 40: 231-236, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33183542

RESUMO

BACKGROUND: Malnutrition, frailty and physical disability are inter-related, more prevalent in the older population and increase the risk of adverse health outcomes. Thus, screening is essential, especially in the understudied care home setting where the population is vulnerable and at higher risk of malnutrition. Furthermore, prevalence may vary depending upon screening tools used. The aims of this study were to: 1) investigate the prevalence of 1) malnutrition risk using Mini Nutritional Assessment - Short Form (MNA-SF) and Malnutrition Universal Screening Tool (MUST), 2) frailty using the Edmonton Frailty Scale (EFS), 3) physical disability using the Barthel Index (BI) and (4) examine the association between variables and coexistence of states. METHODS: Screening for malnutrition (MNA-SF and MUST) and frailty (EFS) was performed as part of a comprehensive geriatric assessment (CGA) in 527 residents from 17 care homes in Lincoln, UK. Mean age of the group was 85.6 ± 7.6 years and body mass index, BMI 23.0 ± 5.1 kg/m2. RESULTS: A high prevalence of malnutrition risk was detected: 41.4% by MNA-SF and 25.5% by MUST (high risk/malnourished). Furthermore, there was a clear discordance between MNA-SF and MUST scoring of malnutrition; for example, the percentage of those identified as being at low risk was 18.8% using the MNA-SF and 57.0% using the MUST. In addition, there was a high prevalence of severe frailty by EFS (69.6%) and functional impairment by BI (62.0%). There was good association between some variables (P < 0.001) and 33.4% of residents had coexistence of all three states of malnutrition, frailty and physical disability. CONCLUSIONS: Malnutrition risk, frailty and physical disability are highly prevalent in care home residents and interrelated. However, prevalence varies depending on the screening tool used. More research should be conducted in the care home setting to improve daily clinical practice as screening may impact upon subsequent treatment and care modalities and clinical outcomes.


Assuntos
Fragilidade , Desnutrição , Idoso , Criança , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Avaliação Geriátrica , Humanos , Desnutrição/diagnóstico , Desnutrição/epidemiologia , Avaliação Nutricional , Prevalência
10.
ACS Nano ; 14(5): 5909-5916, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32310636

RESUMO

Combining atomically thin layers of van der Waals (vdW) materials in a chosen vertical sequence is an emerging route to create devices with desired functionalities. While this method aims to exploit the individual properties of partnering layers, strong interlayer coupling can significantly alter their electronic and optical properties. Here we explored the impact of the vdW epitaxy on electrical transport in atomically thin molybdenum disulfide (MoS2) when it forms a vdW dimer with crystalline films of hexagonal boron nitride (hBN). We observe a thermal history-dependent long-term (over ∼40 h) current relaxation in the overlap region of MoS2/hBN heterostructures, which is absent in bare MoS2 layers (or homoepitaxial MoS2/MoS2 dimers) on the same substrate. Concurrent relaxation in the low-frequency Raman modes in MoS2 in the heterostructure region suggests a slow structural relaxation between trigonal and octahedral polymorphs of MoS2 as a likely driving mechanism that also results in inhomogeneous charge distribution in the MoS2 layer. Our experiment yields an aspect of vdW heteroepitaxy that can be generic to electrical devices with atomically thin transition-metal dichalcogenides.

11.
BMJ Open ; 10(2): e034269, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32075839

RESUMO

OBJECTIVES: To evaluate patient follow-up and complexity in cancer clinical trial delivery, using consensus methods to: (1) identify research professionals' priorities, (2) understand localised challenges, (3) define study complexity and workloads supporting the development of a trial rating and complexity assessment tool (TRACAT). DESIGN: A classic eDelphi completed in three rounds, conducted as the launch study to a multiphase national project (evaluating follow-up and complexity in cancer clinical trials). SETTING: Multicentre online survey involving professionals at National Health Service secondary care hospital sites in Scotland and England varied in scale, geographical location and patient populations. PARTICIPANTS: Principal investigators at 13 hospitals across nine clinical research networks recruited 33 participants using pre-defined eligibility criteria to form a multidisciplinary panel. MAIN OUTCOME MEASURES: Statements achieving a consensus level of 70% on a 7-point Likert-type scale and ranked trial rating indicators (TRIs) developed by research professionals. RESULTS: The panel developed 75 consensus statements illustrating factors contributing to complexity, follow-up intensity and operational performance in trial delivery, and specified 14 ranked TRIs. Seven open questions in the first qualitative round generated 531 individual statements. Iterative survey rounds returned rates of 82%, 82% and 93%. CONCLUSIONS: Clinical trials operate within a dynamic, complex healthcare and innovation system where rapid scientific advances present opportunities and challenges for delivery organisations and professionals. Panellists highlighted cultural and organisational factors limiting the profession's potential to support growing trial complexity and patient follow-up. Enhanced communication, interoperability, funding and capacity have emerged as key priorities. Future operational models should test dialectic Singerian-based approaches respecting open dialogue and shared values. Research capacity building should prioritise innovative, collaborative approaches embedding validated review and evaluation models to understand changing operational needs and challenges. TRACAT provides a mechanism for continual knowledge assimilation to improve decision-making.


Assuntos
Ensaios Clínicos como Assunto , Neoplasias , Medicina Estatal , Adulto , Técnica Delphi , Inglaterra , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/terapia , Escócia , Inquéritos e Questionários
12.
Oman Med J ; 34(5): 412-419, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31555417

RESUMO

OBJECTIVES: Breast cancer (BC) is the leading cancer among women. Almost 20% of patients develop brain metastases (BM) and die shortly afterward. There is a dearth of data on the survival outcome of BC patients with BM from the Arab world. METHODS: Consecutive women diagnosed with BC who developed radiologically-confirmed BM during their illness were identified through the hospital's electronic patient's records. Clinicopathological features and treatment outcomes were recorded. Survival was calculated using the Kaplan-Meier method, and factors affecting survival were studied using log-rank analysis. RESULTS: Between January 2003 and June 2015, a total of 692 patients were treated for BC at our institute. Forty-eight (6.9%) developed BM. The median age at the diagnosis of BM was 45.2 years. More than half of cohort (54.2%) had HER2 positive disease, while 27.1% had the triple-negative disease. The median time interval between the diagnosis of BC and the development of BM was 21 months, and median survival after development of brain disease was seven months. On univariate analysis, pathological grade, previous systemic treatment, brain as the first site of metastases, brain as the only site of metastases, treatment of BM, systemic treatment after BM, and diagnosis-specific graded prognostic assessment (DS-GPA) score significantly affected survival. On multivariate Cox regression analysis, the brain as the first site of metastases, treatment for brain disease, treatment type, and DS-GPA score significantly affected survival post-BM. CONCLUSIONS: Our data indicate that Omani women are diagnosed with BC at a younger age, develop BM earlier, and carry a poor outcome.

13.
J Ayub Med Coll Abbottabad ; 31(3): 355-358, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31535505

RESUMO

BACKGROUND: Anorectal fistula is a common illness which is seen among the middle-aged male patients. Various surgical procedures have been proposed and are associated with the recurrence of the fistula, repeated surgery and in some cases incontinence which may reach up to 43% in complicated fistulas. The purpose of this study was to assess and formulate a non-surgical procedure for fistula in ano through irrigation of the fistula tract with 1% of silver nitrate solution in healing the low perianal fistula. METHODS: Seventy-nine patients presenting to the outpatient department of Ward 3, Surgical unit 1 in Jinnah Postgraduate Medical Centre during a period of 8 months from April to November 2017 with complain of perianal pain and pussy discharge were included in the study. Three patients of the total 79 patients lost to follow up. Outcome measure were cessation of the symptoms for consecutive 10 weeks. RESULTS: Seventy-six patients were assessed and underwent irrigation using this 1% of silver nitrate solution. Out of 76 patients, 58 (76.3%) patients showed complete clinical healing while 18 (23.68%) of patients showed failure to clinical healing. Patients with continuous discharge had a significantly higher rate of complete clinical healing than those with intermittent discharge. CONCLUSIONS: From this study it can be concluded that cauterizing and corrosive properties of silver nitrate are effective in treating the patients with low lying perianal fistula. We suggest that this method should be used as a first line treatment option for all the patients presenting with low lying anal fistula since it is simple, can be easily performed on an OPD basis is minimally invasive and avoids any complication.


Assuntos
Fístula Retal/tratamento farmacológico , Nitrato de Prata/uso terapêutico , Humanos , Resultado do Tratamento
14.
Nanotechnology ; 30(39): 395704, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31247605

RESUMO

Graphene constitutes one of the key elements in many functional van der Waals heterostructures. However, it has negligible optical visibility due to its monolayer nature. Here we study the visibility of graphene in various van der Waals heterostructures and include the effects of the source spectrum, oblique incidence and the spectral sensitivity of the detector to obtain a realistic model. A visibility experiment is performed at different wavelengths, resulting in a very good agreement with our calculations. This allows us to reliably predict the conditions for better visibility of graphene in van der Waals heterostructures. The framework and the codes provided in this work can be extended to study the visibility of any 2D material within an arbitrary van der Waals heterostructure.

15.
Cureus ; 10(11): e3604, 2018 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-30680265

RESUMO

Introduction Abdominal injuries are responsible for 10% of the mortalities due to trauma. Delays in early diagnosis or misdiagnoses are two major reasons for the mortality and morbidity associated with abdominal trauma. The objectives of this study were to determine the frequency of visceral injuries in patients with abdominal trauma and compare the frequency of visceral injuries in patients with blunt and penetrating abdominal trauma. Methods We conducted a cross-sectional study from May 2016 to May 2018 of patients presenting to the emergency department (ED) at Jinnah Postgraduate Medical Center in Karachi, Pakistan. Patients were 12 to 65 years old and presented within 24 hours of abdominal trauma. We recorded the type of abdominal visceral injuries, such as liver, spleen, intestine, stomach, mesentery, and pancreas. Results The mean patient age was 31 ±13 years. Penetrating trauma was found in most patients (n=72, 51%). Liver injuries were found in 37 patients (26.4%), spleen injuries in 29 patient (20.7%), stomach injuries in eight patients (5.7%), intestine injuries in 67 patients (47.9%), mesentery injuries in 21 patients (15%), and pancreas injuries in nine patients (6.4%). The type of abdominal trauma was found significantly associated with liver injury (p-value 0.021), and intestine injury (p-value <0.001). Conclusion Penetrating trauma (51.4%) was more common than blunt trauma (48.5%), and intestines are the most commonly affected by penetrating and blunt trauma injuries (70.1% and 47.8%, respectively). The liver is the most commonly affected (42.85%) in blunt trauma injuries, followed by the spleen (28.5%). The appropriate authorities should consider this information when instituting public health and safety initiatives.

16.
Adv Mater ; 30(2)2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29164707

RESUMO

Van der Waals hybrids of graphene and transition metal dichalcogenides exhibit an extremely large response to optical excitation, yet counting of photons with single-photon resolution is not achieved. Here, a dual-gated bilayer graphene (BLG) and molybdenum disulphide (MoS2 ) hybrid are demonstrated, where opening a band gap in the BLG allows extremely low channel (receiver) noise and large optical gain (≈1010 ) simultaneously. The resulting device is capable of unambiguous determination of the Poissonian emission statistics of an optical source with single-photon resolution at an operating temperature of 80 K, dark count rate 0.07 Hz, and linear dynamic range of ≈40 dB. Single-shot number-resolved single-photon detection with van der Waals heterostructures may impact multiple technologies, including the linear optical quantum computation.

17.
Biochim Biophys Acta ; 1668(2): 164-74, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15737327

RESUMO

We report the protein isolation, cloning and characterization of members of an unusual protein family, which comprise the most abundant proteins present in the squid eye. The proteins in this family have a range of molecular weights from 32 to 36 kDa. Electron microscopy and detergent solubilization demonstrate that these proteins are tightly associated with membrane structures where they may form tetramers. Despite this, these proteins have no stretches of hydrophobic residues that could form typical transmembrane domains. They share an unusual protein sequence rich in methionine, and contain multiple repeating motifs. We have therefore named these proteins Methionine-Rich Repeat Proteins (MRRPs). The use of structure prediction algorithms suggest very little recognized secondary structure elements. At the time of cloning no sequence or structural homologues have been found in any database. We have isolated three closely related cDNA clones from the MRRP family. Coupled in vitro transcription/translation of the MRRP clones shows that they encode proteins with molecular masses similar to components of native MRRPs. Immunoblot analysis of these proteins reveals that they are also present in squid brain, optic lobe, and heart, and also indicate that MRRP-like protein motifs may also exist in mammalian tissues. We propose that MRRPs define a family of important proteins that have an unusual mode of attachment or insertion into cell membranes and are found in evolutionarily diverse organisms.


Assuntos
Membrana Celular/fisiologia , Membrana Celular/ultraestrutura , Olho/metabolismo , Olho/ultraestrutura , Proteínas de Membrana/metabolismo , Proteínas de Membrana/ultraestrutura , Metionina/metabolismo , Sequência de Aminoácidos , Animais , Células Cultivadas , Decapodiformes , Proteínas de Membrana/química , Metionina/química , Dados de Sequência Molecular , Sequências Repetitivas de Aminoácidos/fisiologia , Distribuição Tecidual
18.
Hum Mol Genet ; 11(9): 1005-16, 2002 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11978760

RESUMO

We introduced a targeted single base deletion at codon 307 of the rds-peripherin gene in mice, similar mutations being known to cause autosomal dominant retinitis pigmentosa (RP) in man. Histopathological and electroretinographic analysis indicate that the retinopathy in mice homozygous for the codon 307 mutation appears more rapid than that in the naturally occurring null mutant, the rds(-/-) mouse, suggesting that the rds-307 mutation displays a dominant negative phenotype in combination with that due to haplosufficiency. RP is the most prevalent cause of registered visual handicap in those of working age in developed countries, the 50 or so mutations so far identified within the RDS-peripherin gene accounting for up to 10% of dominant cases of the disease. Given the sequence homologies that exist between the murine rds-peripherin and the human RDS-peripherin gene, this disease model, the first to be generated for peripherin-based RP using gene targeting techniques, should in principle be of value in the work-up in mice of therapeutics capable of targeting transcripts derived from the human gene.


Assuntos
Proteínas do Olho/genética , Deleção de Genes , Proteínas de Filamentos Intermediários/genética , Glicoproteínas de Membrana , Proteínas do Tecido Nervoso/genética , Retinose Pigmentar/genética , Sequência de Aminoácidos , Animais , Códon/genética , Primers do DNA/química , Modelos Animais de Doenças , Eletrorretinografia , Feminino , Marcação de Genes , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Dados de Sequência Molecular , Periferinas , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Retinose Pigmentar/patologia , Homologia de Sequência de Aminoácidos
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