Small interfering RNAs inhibit infectious bursal disease virus replication in Vero cells

Small interfering RNA (siRNA) molecules are considered to be a promising antiviral therapeutics. This study was performed to analyze the application of siRNA against infectious bursal disease virus (IBDV) replication. Two siRNAs were designed to target common coding sequences of four IBDV proteins. Corresponding vectors were constructed to express anti-IBDV short hairpin RNAs (shRNA) that were tested for their antiviral effect in Vero cells. The results showed that expressed shRNA inhibited the virus replication to a significant extent (92%) as determined by the virus titration in cell culture. This outcome demonstrated the effectiveness of RNA interference (RNAi) based mechanism against the IBDV in vitro.

Changing microbiological profile of pathogenic bacteria in diabetic foot infections: time for a rethink on which empirical therapy to choose?

AIMS/HYPOTHESIS

We studied the bacterial aetiology and antibiotic sensitivity pattern of diabetic foot ulcers in India.

METHODS

Records of 447 hospitalised patients between 1991 and 2008 were retrospectively analysed between two time periods (before and after 1999) to compare bacterial aetiology and antimicrobial sensitivity patterns. The first three consecutive cultures from the same wound during treatment were evaluated.

RESULTS

Of 1,632 cultures, 66% were polymicrobial, 23% monomicrobial and 11% sterile. In the monomicrobial group, 14% (n = 228) of cultures were Gram-negative, whereas 9% (n = 147) were Gram-positive. The most common pathogens in the first culture were Pseudomonas aeruginosa (20.1%), Staphylococcus aureus (17.2%) and Escherichia coli (16.3%). Results for the third cultures showed persistence of P. aeruginosa (15.3%) and E. coli (14.2%). Gram-negative isolates dominated over Gram-positive ones (25.3% vs 15.1%, p < 0.05). Antibiotic sensitivity patterns before and after 1999 were: piperacillin-tazobactam 74% vs 66% (p < 0.005), imipenem 77% vs 85% (NS), cefoperazone-sulbactam 47% vs 44% (p < 0.005), amikacin 62% vs 78% (NS), ceftriaxone 41% vs 36% (p < 0.005), amoxicillin-clavulanate 51% vs 43% (p < 0.05) and clindamycin 43% vs 36% (p < 0.005), respectively.

CONCLUSIONS/INTERPRETATION

Unlike in the West, in India Gram-negative bacteria were found to have always been dominant in the wounds of patients with diabetic foot infections. Infection with polymicrobial multidrug-resistant Gram-negative bacilli is common. The policy of empirical antimicrobial therapy at tertiary care needs to be changed.

Percutaneous ultrasound-guided renal biopsy: A Libyan experience

This study was done to assess the safety and efficacy of ultrasound-guided percutaneous renal biopsy (PRB), to ascertain the risk factors for complications and determine the optimal period of observation. The radiologist (A.M.) at the National Organ Transplant Centre, Central Hospital, Tripoli, Libya, performed 86 PRBs between February 1, 2006, and January 31, 2008, using an automated biopsy gun with 16-gauge needle. Coagulation profile was done in all the patients. All patients were kept on strict bed rest for six hours post-procedure. Eighty six renal biopsies were performed on 78 patients referred from rheumatology department and eight post-kidney transplant recipients; 23 were males with age range 15 – 56 years and 63 females with age range 16 – 66 years. A mean of 17.5 glomeruli were present in each specimen. A glomerular yield of less than five glomeruli was seen in four biopsies. Class I lupus nephritis (LN) was seen in 1 patient, class II lupus nephritis in 7 patients, class III LN in 13 patients and class IV LN in 29 patients. All the eight renal allografts were diagnosed as acute tubular necrosis or acute interstitial rejection. The risk of post-biopsy bleeding was higher in women, older patients and higher PTT. The overall complication rate was 5.8%. Three complications were observed within six hours of biopsy. No late complication was seen. PRB under real-time ultrasound-guidance is a safe and efficacious procedure to establish the histological diagnosis and should be done as out-patient procedure. Observation time of six hours post-biopsy is optimal.

Development of repaglinide loaded solid lipid nanocarrier: selection of fabrication method

Repaglinide solid lipid nanoparticles (RG-SLN) were fabricated using stearic acid as lipid. Pluronic F68 (PLF68) and soya lecithin were used as a stabilizer. SLNs were prepared by modified solvent injection and ultrasonication methods. SLNs prepared with modified solvent injection method have larger particle size (360+/-2.5nm) than prepared with ultrasonication method (281+/-5.3nm). The zeta potential of the prepared formulations by these two methods varied from - 23.10 +/-1.23 to -26.01 +/-0.89 mV. The maximum entrapment efficiency (62.14 +/-1.29%) was obtained in modified solvent injection method. The total drug content was nearly same (98%) in both the methods. In vitro release studies were performed in phosphate buffer (pH 6.8) with 0.5% sodium lauryl sulphate (SLS) using dialysis bag diffusion technique. The cumulative drug release was 30% and 50% within 2 hrs in modified solvent injection and ultrasonication method, respectively. This indicates that RG-SLN prepared from modified injection method released the drug more slowly than SLNs prepared with ultrasonication method. Differential scanning calorimetry indicates that repaglinide (RG) entrapped in the solid lipid nanoparticles (SLN) exist in an amorphous or molecular state. Repaglinide loaded solid lipid nanoparticles prepared with both methods were of spherical shape as observed by transmission electron microscopy (TEM). These results suggest that modified solvent injection method is more suitable for preparation of repaglinide SLNs using stearic acid.

A review on scientific technologies in practice to innovate plant based molecules and to improve herbal drug quality to overcome health problems

Medicines obtained from drug plants and other sources are commonly called traditional medicines. They have played an important role in the treatment of several human diseases since ancient times. India possessed a great wealth of traditional health care system known as Ayurveda related to the use of plant species. The global market of herbal drugs has a great potential around the world. Demand of plant based medicines is also increasing among western countries because of a general consideration that most allopathic drugs are associated with more or less side effects. Many pharmaceutical companies are now manufacturing Ayurvedic phytopharmaceutical products. However, enough efforts have not been made to get suitable substitute of modern allopathic medicines from these traditionally used drug plants and herbal drugs. This traditional system of healthcare in India still needs extensive evidence-based scientific researches in promoting its therapies. This review paper deals with modern scientific approaches to find out new plant based molecules and to develop new technologies in a continuous process and should be applied in the practice to improve the quality of herbal drugs in Indian pharmaceutical industries. Critical assessment of quality assurance including researches on pharmacognosy, chemistry, pharmacology, antimicrobial activity and clinical studies carried out on various Ayurvedic medicinal plants are also being presented.

Mirror foot--a reflection on three cases

INTRODUCTION AND AIMS

Mirror-foot abnormalities are distinctly uncommon entities and represent extreme forms of congenital duplication. We present a reflection on three different cases of mirror foot and discuss their surgical management.

PATIENTS AND METHODS

The first patient had a right-sided mirror foot with a central great toe and three complete medial rays. The second patient had quadruplication of the left great toe ray. The third had a full complement of metatarsals associated with two extra complete rays placed medial to the great toe of the right foot. All patients underwent complex ray resection and concurrent reconstruction of the medial arch of foot. All three cases of mirror foot presented and were operated on in the pre-ambulatory period.

RESULTS

All three patients recovered with good functional and aesthetic results. Follow-up duration ranged from 3 to 5 years.

CONCLUSION

Surgical treatment of the mirror foot is less complicated than that of its upper limb equivalent. Essentially, there must be an initial surgical reduction in the number of digits, coupled with tendon transfers as necessary to maintain foot arches.

Highly efficient photocathodes for dye-sensitized tandem solar cells

Thin-film dye-sensitized solar cells (DSCs) based on mesoporous semiconductor electrodes are low-cost alternatives to conventional silicon devices. High-efficiency DSCs typically operate as photoanodes (n-DSCs), where photocurrents result from dye-sensitized electron injection into n-type semiconductors. Dye-sensitized photocathodes (p-DSCs) operate in an inverse mode, where dye-excitation is followed by rapid electron transfer from a p-type semiconductor to the dye (dye-sensitized hole injection). Such p-DSCs and n-DSCs can be combined to construct tandem solar cells (pn-DSCs) with a theoretical efficiency limitation well beyond that of single-junction DSCs (ref. 4). Nevertheless, the efficiencies of such tandem pn-DSCs have so far been hampered by the poor performance of the available p-DSCs (refs 3, 5-15). Here we show for the first time that p-DSCs can convert absorbed photons to electrons with yields of up to 96%, resulting in a sevenfold increase in energy conversion efficiency compared with previously reported photocathodes. The donor-acceptor dyes, studied as photocathodic sensitizers, comprise a variable-length oligothiophene bridge, which provides control over the spatial separation of the photogenerated charge carriers. As a result, charge recombination is decelerated by several orders of magnitude and tandem pn-DSCs can be constructed that exceed the efficiency of their individual components.

Circuit techniques for wireless brain interfaces

Efficient, miniaturized wireless recording is critical for both existing and emerging health-monitoring applications. One important example of this is in the brain interface community, where new technologies allow improved observation and understanding of brain functions. This, in turn, drives the need for ever smaller, lower power, and higher performance circuitry for chronic recording. This paper describes circuit and system techniques for low power wireless brain interfaces. Active and passive architectures are described and compared, and measured in-vivo data from both are presented.

The suction pseudopolyp technique: a novel method for the removal of small flat nonpolypoid lesions of the colon and rectum

BACKGROUND AND STUDY AIMS

Small flat nonpolypoid lesions of the colorectum can be technically difficult to target and completely remove; techniques such as hot biopsy forceps electrocauterization are associated with serositis, delayed bleeding, and perforation. This study aimed to describe a novel technique for the removal of such lesions and demonstrate its safety and efficacy.

PATIENTS AND METHODS

Patients aged 18 - 80 years with flat nonpolypoid lesions (Paris-Japanese classification 0-IIa and 0-IIb, measuring less than 10 mm) identified at colonoscopy were included in this prospective study. The lesions were removed by the suction pseudopolyp technique (SPT): the lesion is aspirated into the suction channel of the colonoscope and continuous suction applied for 5 seconds whilst the colonoscope is gently retracted. On release of the suction, the resulting pseudopolyp containing the lesion and a margin of normal tissue is easily ensnared and resected. The primary outcomes were endoscopic completeness of polyp resection and complication rate.

RESULTS

Over a 12-month period, 1231 polyps were removed during 2656 colonoscopies; 126 polyps (in 101 patients) met inclusion criteria. Complete endoscopic resection was achieved in 100 % of the polyps, without immediate or delayed complication. Of the resected lesions, 57 % had malignant potential (adenomas 47 % and sessile serrated lesions 10 %); a higher proportion of lesions removed from the right colon had malignant potential compared with those from the left colon (75 % vs. 41 %, P = 0.0066).

CONCLUSIONS

Diminutive flat lesions of the colorectum are predominantly adenomas and sessile serrated lesions. SPT is a safe, effective, and reproducible therapy for removal of these lesions.

Approach and safety of comprehensive central compartment dissection in patients with recurrent papillary thyroid carcinoma

BACKGROUND

Despite the generally favorable prognosis of patients with papillary thyroid cancers, 10-year recurrence rates for patients with stage I to III disease is greater than 20%, with central compartment recurrences common among these recurrent sites.

METHODS

This study is a retrospective analysis of consecutive patients treated by a single surgeon over an 18-month period of time terminating in 2003.

RESULTS

Sixty-three patients underwent a comprehensive dissection of levels VI and VII for papillary thyroid carcinoma during this period. There was a female predominance of 2:1, with 48% of patients being greater than 45 years of age. The median number of lymph nodes identified was 16 (range, 3-52), with 7 (1-20) lymph nodes pathologically involved. Permanent hypoparathyroidism was present on presentation in 13% of patients and developed in an additional 5% following surgery. Although recurrent laryngeal paralysis was present on presentation among 8 (13%) of patients, no patients experienced paralysis of documented functioning recurrent laryngeal nerves or necessitated tracheotomy. Postoperative thyroglobulin levels were reduced to nondetectable in 71% of the informative cases. Over 60% of patients were discharged on their first postoperative day.

CONCLUSION

Bilateral paratracheal and superior mediastinal dissection is an oncologically safe procedure exhibiting minimal morbidity when performed among experienced individuals despite multiple prior surgical procedures or existing vocal cord paralysis.