CRISPR-Cas9 Applications in Cardiovascular Disease.

The CRISPR-Cas9 system is an economical and accessible gene-editing technology first discovered as a naturally occurring bacterial immune system. Since its fairly recent discovery, CRISPR-Cas9 system's efficiency and simplicity have been successfully used to edit genomes of living organisms in many fields, working in vitro and in vivo in germline and somatic cells to knock-out harmful mutated genes or in some cases working to knock-in a beneficial gene. A current application of the gene-editing system works against specific mutations that cause certain cardiovascular diseases. However, there are current technical limitations as well as ethical dilemmas in introducing gene-editing to humans. Here, we explore highlights on the current state of research of the CRISPR-Cas9 system through the lens of cardiovascular disease and examine potential untouched applications of the system in the field of cardiology.

Multimodal Evaluation of TMS - Induced Somatosensory Plasticity and Behavioral Recovery in Rats With Contusion Spinal Cord Injury.

Introduction: Spinal cord injury (SCI) causes partial or complete damage to sensory and motor pathways and induces immediate changes in cortical function. Current rehabilitative strategies do not address this early alteration, therefore impacting the degree of neuroplasticity and subsequent recovery. The following study aims to test if a non-invasive brain stimulation technique such as repetitive transcranial magnetic stimulation (rTMS) is effective in promoting plasticity and rehabilitation, and can be used as an early intervention strategy in a rat model of SCI. Methods: A contusion SCI was induced at segment T9 in adult rats. An rTMS coil was positioned over the brain to deliver high frequency stimulation. Behavior, motor and sensory functions were tested in three groups: SCI rats that received high-frequency (20 Hz) rTMS within 10 min post-injury (acute-TMS; n = 7); SCI rats that received TMS starting 2 weeks post-injury (chronic-TMS; n = 5), and SCI rats that received sham TMS (no-TMS, n = 5). Locomotion was evaluated by the Basso, Beattie, and Bresnahan (BBB) and gridwalk tests. Motor evoked potentials (MEP) were recorded from the forepaw across all groups to measure integrity of motor pathways. Functional MRI (fMRI) responses to contralateral tactile hindlimb stimulation were measured in an 11.7T horizontal bore small-animal scanner. Results: The acute-TMS group demonstrated the fastest improvements in locomotor performance in both the BBB and gridwalk tests compared to chronic and no-TMS groups. MEP responses from forepaw showed significantly greater difference in the inter-peak latency between acute-TMS and no-TMS groups, suggesting increases in motor function. Finally, the acute-TMS group showed increased fMRI-evoked responses to hindlimb stimulation over the right and left hindlimb (LHL) primary somatosensory representations (S1), respectively; the chronic-TMS group showed moderate sensory responses in comparison, and the no-TMS group exhibited the lowest sensory responses to both hindlimbs. Conclusion: The results suggest that rTMS therapy beginning in the acute phase after SCI promotes neuroplasticity and is an effective rehabilitative approach in a rat model of SCI.

Does Capsular Laxity Lead to Microinstability of the Native Hip?

BACKGROUND: Hip "microinstability" is commonly cited as the cause of symptoms that occur in the presence of translation of the femoral head away from conformity with the acetabular fossa. However, there is still no consistent objective criteria defining its presence and biomechanical basis. One hypothesis is that abnormal motion of the articular surfaces occurs because of capsular laxity, ultimately leading to clinical symptoms. PURPOSE: To determine the relationship between capsular laxity and abnormal rotation and translation of the hip. STUDY DESIGN: Controlled laboratory study. METHODS: Eight cadaveric hips were dissected down to the capsule and mounted in a customized multiaxial hip activity simulator. Each specimen was loaded with 5 N·m of internal and external rotational torque in full extension and 0°, 30°, 60°, and 90° of flexion. During testing, the relative position and rotation of the femur and the pelvis were monitored in real time with a 6-camera motion analysis system. The testing was repeated after capsular laxity was generated by placing a regular array of incisions ("pie crusting") in the iliofemoral, pubofemoral, and ischiofemoral ligaments. Joint rotation and femoral head translation were calculated with specimen-specific models. A hip microinstability index was defined as the ratio between the length of the locus of the femoral head center and the radius of the femoral head during rotation from extension to 90° of flexion. RESULTS: In intact hips, the components of femoral head translation were within 0.5 mm in positions close to neutral (<30° of flexion). Capsular modification led to significant increases in internal and external rotation ( P < .01) and in the translation of the femoral head center at different positions ( P < .05). Compared with intact hips, the femoral head was inferiorly displaced during external rotation and anteroinferiorly during internal rotation. The length of the locus of the femoral head center increased from 3.61 ± 1.30 mm to 5.35 ± 1.83 mm for external rotation ( P < .05) and from 6.24 ± 1.48 mm to 8.21 ± 1.42 mm for internal rotation ( P < .01). The correlations between rotational laxity and the total translation of the femoral head were not significant, with coefficients of 0.093 and 0.006 in external and internal rotation, respectively. In addition, the hip microinstability index increased from 0.40 ± 0.08 for intact hips to 0.55 ± 0.09 for modified hips ( P < .01). CONCLUSION: The native hip approximates a concentric ball-and-socket joint within 30° of flexion; however, beyond 30° of flexion, the femoral head translation reached as high as 4 mm. Capsular laxity leads to microinstability of the hip, as indicated by significantly increased joint rotations and femoral head translations and an abnormal movement path of the femoral head center. However, there was no correlation between rotational laxity and the increase in femoral head translation. CLINICAL RELEVANCE: Capsular laxity alters normal kinematics (joint rotation and femoral head translation) of the hip, potentially leading to abnormal femoral-acetabular contact and joint degeneration.

Hypothermia in Total Joint Arthroplasty: A Wake-Up Call.

BACKGROUND: Total joint patients are particularly vulnerable to perioperative hypothermia (PH) (combined effects of anesthesia, radiation, and convective heat loss from exposed skin surfaces and cool temperatures in the operating room). There are limited studies on PH in these patients. METHODS: In a retrospective review of 204 patients undergoing primary hip and 179 undergoing primary knee replacement surgeries, time and temperature parameters were collected from the electronic health records from preoperative and postoperative recovery room nursing assessments, intraoperative anesthesia records, and floor nursing notes. Basic patient demographic data was recorded. Chi-squared and paired t-tests were used to compare between hypothermic and normothermic groups. RESULTS: At the time of incision, 60 of 179 (34%) total knee arthroplasty (TKA) patients and 80 of 204 (39%) total hip arthroplasty (THA) patients were hypothermic. In THA patients, 65% remained hypothermic for the duration of anesthesia compared to 33% of TKA patients. The largest drop in core body temperature in both THA and TKA patients occurred between preoperative holding and induction of anesthesia. In THA patients, spinal anesthesia had a significantly higher occurrence of PH. No significant patient factor was found to increase risk. CONCLUSION: Emphasis on preoperative holding protocols, decreasing time from operating room entry to incision, and increasing ambient room temperature could reduce risk of hypothermia in total joint replacement patients.

Inferior angle of scapula fractures: a review of literature and evidence-based treatment guidelines.

BACKGROUND: Inferior angle of scapula (IAS) fractures are rare, with very few cases reported. They typically present with pain, loss of shoulder motion, and scapula winging. Operative and nonoperative treatments have been trialed with varying success. The aim of this study was to gather data relating to IAS fractures to develop evidence-based treatment guidelines as none are currently available. METHODS: A search was conducted of the PubMed and Google Scholar databases to identify cases of IAS fractures. Data collected about each case included age and gender of the patient, mechanism of injury, fracture displacement, treatment, and outcome. The authors report 2 additional IAS fracture cases. RESULTS: Ten cases were identified for inclusion in this study, 8 from the literature and 2 described by the authors. Of the 10 cases, 7 described displaced IAS fractures and 3 described undisplaced fractures. All displaced fractures treated nonoperatively resulted in a painful nonunion. All that underwent operative fixation, whether acutely or after failed nonoperative treatment, had resolution of pain and a good functional outcome. All undisplaced fractures were treated nonoperatively; 1 had persisting pain. Surgical exploration identified the fracture fragment attached to serratus anterior in 2 cases and attached to both serratus anterior and latissimus dorsi in 2 cases. DISCUSSION AND CONCLUSIONS: There are limited data available about IAS factures. From the cases reviewed, treatment recommendations include the following: (1) displaced IAS fractures should undergo operative fixation to prevent the development of a painful nonunion; (2) suture repair provides adequate fixation; and (3) undisplaced fractures have a variable outcome when treated nonoperatively.

Assessment of Microleakage in Class II Cavities having Gingival Wall in Cementum using Three Different Posterior Composites.

BACKGROUND: Dental composites are one of the most desired restorative materials today. Composite materials can be bonded successfully to human tooth enamel; however, developing the same degree of adhesion to dentin or cementum is a more challenging task. Polymerization contraction stress of dental composites is often associated with marginal and interfacial failures of bonded restorations. The magnitude of stress depends on composite composition and its ability to flow before gelation, which is related to the cavity configuration and curing characteristics of the composite. MATERIALS AND METHODS: This study was carried out on 24 extracted human molars and divided into three groups. Class II (slot) cavities were prepared on the mesial and distal surfaces of the teeth with the gingival wall in dentin/cementum, and the microleakage was observed. After preparation the teeth were randomly assigned into three groups of eight specimens each. The cavities were restored with: Group 1: Packable composite (Surefil, Dentsply); Group 2: Hybrid composite (Filtek Z250, 3M Dental Products); Group 3: Nanocomposite (Filtek Z350, 3M Dental Products). Sixteen samples of each group were subjected to 500 cycles of thermocycling between 5°C and 55°C. All the teeth were immersed in methylene blue for 8 h and then left in tap water for 12 h. The teeth were sectioned mesiodistally with a diamond disc, and examined under a stereomicroscope. RESULTS: The analysis indicated that packable composite showed more microleakage than all the other groups. Hybrid composite showed less microleakage than packable composite, but more leakage than nanocomposite. CONCLUSION: All composites under the study exhibited a certain amount of microleakage in the dentin/cementum margin. Packable composite showed the most microleakage and nanocomposite showed least microleakage. Since these results were obtained in vitro, long-term clinical trials are needed to fully understand the performance of these materials.

Prevalence of gingival enlargement in Karnataka school going children.

BACKGROUND: Periodontal diseases affect more people all over the world than dental caries. Increase in size of gingiva is known as gingival hyperplasia or gingival enlargement. Gingival swelling is almost universally the result of Fluid accumulation within the tissues. Enlargement and even aesthetically disfiguring over growth of the gingival tissue, is also a common finding of leukemia, scurvy and subjects undergoing the hormonal changes of puberty, pregnancy, menopause and drugs. MATERIALS & METHODS: A sample size of 1500 was taken. All children who were between the chronological age of 5-12 years from selected schools were included in the study.Three age groups were selected for the study, Group I: 5-7yrs, Group II: 7-9 yrs, Group III 9-12yrs. Each group comprised of 500 students. The examination of gingival enlargement was made according to Gingival Enlargement Index. The oral hygiene status of the child was examined using Oral Hygiene Index-Simplified. RESULTS: The prevalence of Gingival Enlargement increased with the increase of age. Though the Prevalence of GE in female children (15.1%) was more than male children (13.4%), it was not statistically significant. Female children (1.6%) had a higher prevalence of epilepsy than male children (0.29%) in this present study. CONCLUSION: The prevalence of gingival enlargement was predominantly inflammatory, showing that the oral hygiene status of the oral Children in Karnataka was far from satisfactory. Further studies need to be undertaken regarding the prevalence if GE in School going children. How to cite the article: Krishna KB, Raju PK, Chitturi RR, Smitha G, Vijai S, Srinivas BV. Prevalence of gingival enlargement in Karnataka school going children. J Int Oral Health 2014;6(1):106-10.

Laparoendoscopic approach for refractory Roux-en-Y hepaticojejunostomy stricture in an acute setting: a unique case and technique.

Roux-en-Y hepaticojejunostomy stricture is a substantial problem that develops in 10%-30% of patients and requires frequent intervention. Although endoscopic/percutaneous approaches are preferred, especially for refractory stricture, open surgical reconstruction remains the gold standard. However, such an operation may be highly challenging. The recently developed covered, self-expanding metallic stent is a useful option for such difficult cases. We present a case of recurrent Roux-en-Y hepaticojejunostomy stricture complicated by densely packed intrahepatic stones and suppurative cholangitis with failed percutaneous biliary draining. Enteroscopic manipulations were unfeasible, and the case was successfully managed by the laparoendoscopic approach. If treating surgeons have the necessary expertise, this technique may be considered in such difficult scenarios.

"Prevention of structural perturbation and aggregation of hepatitis B surface antigen: screening of various additives".

The instability of protein and antigen(s) during encapsulation in biodegradable polymers by water-in-oil-in-water (w/o/w) encapsulation is well established. The aim of present study is to screen various additives to prevent the inactivation and loss of immunogenicity of HBsAg upon its exposure to the water/CH(2)Cl(2) (methylene chloride) interface by simulating the formulation steps involved in the preparation of microspheres. The secondary structure of HBsAg, recovered under different conditions after primary emulsification, was investigated by FTIR spectroscopy and Circular Dichorism. Subsequently, PLGA microspheres were formulated and characterized for their size, shape, incorporation efficiency, antigen integrity, and immunogenicity. The immunogenicity and the HBsAg recovery under different conditions were tested in BALB/c mice. Inulin and trehalose were found to be better stabilizing agents to prevent the aggregation, the structural perturbations and immunogenicity of HBsAg. This study substantiated that inulin could overcome the aggregation and denaturing effects of the water/CH(2)Cl(2) interface upon HBsAg during emulsification step and upon encapsulation.

Tibial stem tip pain in stemmed revision total knee arthroplasty: treatment with tension band plating.

The use of stemmed modular components in revision total knee arthroplasty has led to increasingly described pain located at the tip of the stem of the implant. This has been described in the literature as being due to the elastic modulus mismatch between the stem tip and the host bone. Current management is re-revision total knee arthroplasty in an attempt to alleviate the mismatch. This case report describes a novel technique using a dynamic compression plate acting as a tension band at the stem tip to successfully treat this condition.

Granuloma debridement and the use of an injectable calcium phosphate bone cement in the treatment of osteolysis in an uncemented total knee replacement.

Polyethylene particulate debris-induced periprosthetic osteolysis is a known complication of knee arthroplasty surgery, and may result in the need for revision surgery. The management of these bony defects can be surgically challenging, and full revisions of well-fixed total knee components can lead to substantial bone loss. We present the case of a 71 year old man who developed knee pain and osteolysis around an uncemented total knee replacement. Due to significant medical comorbidies he was treated by percutaneous cyst granuloma debridement and grafting using an injectable calcium phosphate bone substitute. There were no wound complications, and the patient was allowed to fully weight-bear post-operatively. Histopathology and microbiology of the cyst material confirmed polyethylene granulomata without any evidence of infection. At 6 weeks post-operatively the patient's previous knee pain had resolved, he was able to comfortably fully weight-bear. Preoperative scores (Knee Society Score (KSS) 41, WOMAC score 46.2, and Oxford Knee Score 39) had all improved at the 12-month post-operative review KSS 76, WOMAC 81.7 and Oxford Knee score 21). This is a safe and effective technique with minimal morbidity and may be an appropriate treatment modality when more extensive revision surgery is not possible. The case is discussed with reference to the literature.

Adductor tenotomy: its role in the management of sports-related chronic groin pain.

PATIENTS AND METHODS: Chronic adductor-related groin pain in athletes is debilitating and is often challenging to treat. Little is published on the surgical treatment when conservative measures fail. This single center study reviews the outcomes of 48 patients (68 groins) who underwent percutaneous adductor tenotomy for sports-related chronic groin pain. Questionnaire assessments were made preoperatively and at a minimum follow-up of 25 months. RESULTS: Mean pre-injury Tegner activity scores of 8.8 reduced to 6.1 post-injury and these improved to 7.7 following surgery (p < 0.001). Sixty percent of patients regained or bettered their pre-injury Tegner activity scores after the adductor surgery; however, mean post-surgical Tegner scores still remained lower than pre-injury scores (p < 0.001). No patient had been able to engage in their chosen sport at their full ability pre-operatively, and 40% had been unable to participate in any sporting activity. The mean return to sports was at 18.5 weeks postoperatively, with 54% returning to their pre-injury activity levels, and only 8% still unable to perform athletic activities at latest follow-up. Seventy-three percent patients rated the outcome of their surgery as excellent or very satisfactory, and only three patients would not have wished to undergo the procedure again if symptoms recurred or developed on the opposite side. No patients reported their outcome as worse. A 78.1% mean improvement in function and an 86.5% mean improvement in pain were reported, and these two measures showed statistically significant correlation (p = 0.01). Groin disability scores improved from a mean of 11.8 to 3.9, post-operatively (p < 0.001). Bruising was seen in 37% of procedures, 3 patients developed a scrotal hematoma and 1 patient had a superficial wound infection. One patient developed recurrent symptoms following re-injury 26 months post-surgery, and fully recovered following a further adductor tenotomy. CONCLUSIONS: Adductor tenotomy provides good symptomatic and functional improvement in chronic adductor-related groin pain refractory to conservative treatment.

Chronic asymptomatic dislocation of a total hip replacement: a case report.

INTRODUCTION: Dislocation of a prosthetic hip is the second most common complication after thromboembolic disease in patients undergoing total hip arthroplasty, with an incidence reported as 0.5 to 20%. Although the period of greatest risk for dislocation has been reported to be within the first few months after surgery, late dislocation occurs more commonly then previously thought. CASE PRESENTATION: A 60-year-old man underwent a right Exeter cemented total hip replacement and was subsequently discharged after appropriate follow-up. He next presented 8 years later complaining of pain in the left groin. An anterioposterior radiograph of the pelvis revealed degenerative changes in the left hip and a dislocated right total hip replacement. The dislocated femoral component had formed a neoacetabulum within the ilium, in which it was freely articulating. He remained pain-free on this side, had 5 cm of true leg length shortening with a good range of movement and was very pleased with his hip replacement. He was later placed on the waiting list for a left total hip replacement. CONCLUSION: This case illustrates that a dislocated total hip replacement may occasionally not cause symptoms that cause significant discomfort or reduction in range of movement. The prosthetic femoral head can form a neoacetabulum allowing a full range of pain-free movement. Furthermore it emphasises that with an increased trend to earlier hospital discharge and shorter follow-up, potential complications may be missed. We urge a low index of suspicion for potential complications and suggest that regular review with radiographic follow-up should be made.

Ca(2+) influx through the osteoclastic plasma membrane ryanodine receptor.

We predict that the type 2 ryanodine receptor isoform (RyR-2) located in the osteoclastic membrane functions as a Ca(2+) influx channel and as a divalent cation (Ca(2+)) sensor. Cytosolic Ca(2+) measurements revealed Ca(2+) influx in osteoclasts at depolarized membrane potentials. The cytosolic Ca(2+) change was, as expected, not seen in Ca(2+)-free medium and was blocked by the RyR modulator ryanodine. In contrast, at basal membrane potentials (approximately 25 mV) ryanodine triggered extracellular Ca(2+) influx that was blocked by Ni(2+). In parallel, single-channel recordings obtained from inside-out excised patches revealed a divalent cation-selective approximately 60-pS conductance in symmetric solutions of Ba-aspartate [Ba-Asp; reversal potential (E(rev)) approximately 0 mV]. In the presence of a Ba(2+) gradient, i.e., with Ba-Asp in the pipette and Na-Asp in the bath, channel conductance increased to approximately 120 pS and E(rev) shifted to 21 mV. The conductance was tentatively classified as a RyR-gated Ca(2+) channel as it displayed characteristic metastable states and was sensitive to ruthenium red and a specific anti-RyR antibody, Ab(34). To demonstrate that extracellular Ca(2+) sensing occurred at the osteoclastic surface rather than intracellularly, we performed protease protection assays using pronase. Preincubation with pronase resulted in markedly attenuated cytosolic Ca(2+) signals triggered by either Ni(2+) (5 mM) or Cd(2+) (50 microM). Finally, intracellular application of antiserum Ab(34) potently inhibited divalent cation sensing. Together, these results strongly suggest the existence of 1) a membrane-resident Ca(2+) influx channel sensitive to RyR modulators; 2) an extracellular, as opposed to intracellular, divalent cation activation site; and 3) a cytosolic CaM-binding regulatory site for RyR. It is likely therefore that the surface RyR-2 not only gates Ca(2+) influx but also functions as a sensor for extracellular divalent cations.