An interesting case report of cutaneous tuberculosis of the foot.

INTRODUCTION AND IMPORTANCE: Tuberculosis is an age old disease caused by Mycobacterium tuberculosis which has been a menace to public health and thwarting economic growth. Pulmonary tuberculosis being the most common type, extra pulmonary tuberculosis has a greater association with HIV and multidrug resistant tuberculosis. Cutaneous tuberculosis accounts for 1-1.5 % of extra pulmonary tuberculosis. CASE PRESENTATION: A 32 year old female presented to the outpatient department with a two month history of ulcer over the sole of the foot with multiple discharging sinuses and surrounding induration. Laboratory tests reported elevated total leukocyte counts. Magnetic Resonance Imaging of the foot showed diffuse intermuscular edema with an interconnecting sinus tract draining to the sole of the foot. Regular wound dressings and antibiotics showed no resolution. Patient eventually underwent near complete excision of the ulcer. The biopsy was suggestive of tuberculous etiology. She achieved complete resolution with antituberculous drugs by three months. CLINICAL DISCUSSION: Cutaneous tuberculosis is often misdiagnosed as it can masquerade as many other commonly encountered dermatological conditions. Microbiological diagnosis plays a crucial role in the accurate diagnosis of cutaneous tuberculosis. These lesions are highly responsive to antituberculous drugs. CONCLUSION: Cutaneous tuberculosis is a rare disease that should be considered in the differential diagnosis of patients with chronic non-healing wounds that are poorly responsive to conventional treatment methods.

Processing and mechanical behavior of lamellar structured degradable magnesium-hydroxyapatite implants.

Multilayered (laminated) composites exhibit tunable mechanical behavior compared to bulk materials due to the presence of more interfaces and therefore magnesium based composites are gaining wide popularity as biodegradable materials targeted for temporary implant applications. The objective of the present work is to fabricate magnesium based lamellar metal matrix composites (MMCs) for degradable implant applications. Nano-hydroxyapatite (HA) powder was selected as the secondary phase and lamellar structured magnesium-nano-hydroxyapatite (Mg-HA) composites of 8, 10 and 15wt% HA were fabricated by ball milling and spark plasma sintering. It was found that HA particles were coated on the Mg flakes after 20h of ball milling carried out using tungsten carbide (WC) as the milling media. Spark plasma sintering of the milled powders resulted in the formation of lamellar structure of Mg with the presence of HA and magnesium oxide (MgO) at the inter-lamellar sites of the composites. Phase analysis of the milled powder by an X-ray diffraction (XRD) method confirms the presence of HA and MgO along with Mg after sintering. Corrosion behavior of the composites investigated by potentiodynamic polarization tests shows a reduction in the inter-lamellar corrosion with increase in HA content and the best corrosion resistance is found for the Mg-10% HA composite. This composite also exhibits maximum Vickers hardness. Young׳s modulus and fracture toughness measured by nano-indentation method were higher for the Mg-8% HA composite. The results thus suggest that lamellar structured Mg composites with 8% and 10% HA show promise for temporary degradable orthopedic implant applications because of their improved corrosion resistance and superior mechanical properties.

The primary structure of xylanase from Thermoascus aurantiacus.

The amino acid sequence of xylanase isolated from the culture medium of Thermoascus aurantiacus was determined. It had 269 amino acid residues with an alpha-N-acetyl group at the amino terminus. The structure of blocked N-terminal 11 amino acid tryptic peptide except for acetylalanine was determined by sequence analysis of peptides derived from partial acid hydrolysis and from thermolysin digestion. The blocked N-terminal amino acid was determined as N-acetylalanine by electron ionization mass spectrometry. The sequence comparison of xylanase from T. aurantiacus with the xylanases of alkalophilic Bacillus sp C-125 and Cryptococcus albidus showed 40% similarity. Xylanase from T. aurantiacus had up to 15% similarity with the other two xylanases known. All the five xylanases showed a higher degree of similarity at the level of secondary structure.

Crossed asymmetry in Russell-Silver syndrome.

Since the initial report by Silver et al (1953), more than 50 examples of the Russell-Silver syndrome have been reported. Unilateral congenital asymmetry of the extremities has been considered one of the major features of this disorder (Silver, 1964). We recently observed a child with otherwise typical features of the Russell-Silver syndrome who had enlargement of the right hand and of the left lower extremity. We know of no other recorded example of crossed asymmetry in this clinical entity.