Hypoxis (Hypoxidaceae) in Africa: list of species and infraspecific names

A list of species and synonyms is presented for the African Hypoxis L. An abbreviated reference to the original publication of a species is included in the list. Distribution of taxa is indicated by the country in which they occur. A list of synonyms with accepted or suggested names and the reference to change in status of a taxon is provided. Subsequent publications on the treatment of a taxon are given to denote congruous and differing resolution of taxa by authorities.

Damage Control Surgery for Abdominal Trauma

Damage control is not a modern concept, but the application of this approach represents a new paradigm in surgery, borne out of a need to save patients with severe exsanguinating injuries. Definitive control and repair may be accomplished in the immediate post injury setting but the physiological derangement due to massive shock state resulting from the severe injury and the resuscitation that follows, often leads to a fully repaired but dead patient. The vicious triad of death in trauma, namely hypothermia, acidosis and coagulopathy should be tackled by initial abbreviated laparotomy, correction of physiological derangements and finally definitive repair of all injuries at second laparotomy. The concept needs a dedicated team effort with careful patient selection for achieving the optimal results.

Effect of genome sequence on the force-induced unzipping of a DNA molecule

We considered a dsDNA polymer in which distribution of bases are random at the base pair level but ordered at a length of 18 base pairs and calculated its force elongation behaviour in the constant extension ensemble. The unzipping force F(y) vs. extension y is found to have a series of maxima and minima. By changing base pairs at selected places in the molecule we calculated the change in F(y) curve and found that the change in the value of force is of the order of few pN and the range of the effect depending on the temperature, can spread over several base pairs. We have also discussed briefly how to calculate in the constant force ensemble a pause or a jump in the extension-time curve from the knowledge of F(y).

Statistical theory of force-induced unzipping of DNA

The unzipping transition under the influence of external force of a dsDNA molecule has been studied using the Peyrard-Bishop Hamiltonian. The critical force F(c)(T) for unzipping calculated in the constant force ensemble is found to depend on the potential parameter k which measures the stiffness associated with a single strand of DNA and on D, the well depth of the on-site potential representing the strength of hydrogen bonds in a base pair. The dependence on temperature of F(c)(T) is found to be (T(D) - T)(1/2) (T(D) being the thermal denaturation temperature) with F(c)(T(D)) = 0 and F(c)(0) = [Formula: see text]. We used the constant extension ensemble to calculate the average force F(y) required to stretch a base pair a y distance apart. The value of F(y) needed to stretch a base pair located far away from the ends of a dsDNA molecule is found twice the value of the force needed to stretch a base pair located at one of the ends to the same distance for y >/= 1.0 A. The force F(y) in both cases is found to have a very large value for y approximately 0.2 A compared to the critical force found from the constant force ensemble to which F(y) approaches for large values of y. It is shown that the value of F(y) at the peak depends on the value of krho which measures the energy barrier associated with the reduction in DNA strand rigidity as one passes from dsDNA to ssDNA and on the value of the depth of the on-site potential. The effect of defects on the position and height of the peak in the F(y) curve is investigated by replacing some of the base pairs including the one being stretched by defect base pairs. The formation and behaviour of a loop of Y shape when one of the ends base pair is stretched and a bubble of ssDNA with the shape of "an eye" when a base pair far from ends is stretched are investigated.

Isolation of Mycoplasma bovoculi from genitally diseased bovines and its experimental pathogenicity in pregnant guinea pigs

Thirteen strains of M. bovoculi, 6 from frozen bull-semen (3.5% of 168), 3 from neat bull-semen (3.0% of 100), one each from heart blood and stomach contents of aborted foetus of 85 (1.18%) bovine-abortions, one each from stomach contents and pooled internal organs of 9 (11.1%) stillborn calves, were isolated. All the isolates were resistant to ampicillin and sensitive to spiramycin, vibramycin, demeclocyclin, oxytetracycline, lincomycin and tylosin. However, variation in resistance to tetracycline, erythromycin, neomycin, kanamycin and streptomycin was observed. The gross lesions like congestion of lungs, liver, kidney and spleen were noted only in stillborn calf. However, significant microscopic lesions were encountered in internal tissues of both the aborted bovine fetuses and stillborn calf. Thickened alveolar wall, congestion of blood vessels, mesenchymal cell proliferation along with infiltration of lymphocytes and macrophages were observed in lungs. The liver showed mild infiltration of lymphocytes, macrophages in hepatic triad and necrosis of hepatic cells. The kidney tissues had focal lymphocytic infiltration in the interstitium. One strain of M. bovoculi (isolate # SBC-7/84,IO) isolated from a stillborn calf was found abortigenic upon experimental inoculation in pregnant guinea pigs.

Experimental pathogenicity evaluation of Mycoplasma canadense from bovine mastitis in vitro and in vivo laboratory models

Mycoplasma canadense, a clinical isolate from milk of a mastitic buffalo, was experimentally tested for its pathogenic potential in hamster tracheal ring and rabbit fallopian tube explant organ cultures (in vitro) and rat and rabbit mammary gland (in vivo) models. The activity percentage reduction in M. canadense infected hamster tracheal rings was 99.1% in comparison to 16.4% in control rings. Mycoplasma canadense, also induced complete ciliostasis at 11-day post-infection in rabbit fallopian tube explants. Histopathological lesions in these infected organ cultures were loss of cilia, desquamation or denudation of epithelium, infiltration of inflammatory cells and proliferation of macrophages as well as oedema in lamina propria. At the end of the experiments, M. canadense organisms were reisolated in pure colonies from the infected but not the control organ cultures. In the rat and rabbit mammary glands, M. canadense organisms persisted upto 6-day and 7-day postinfection, respectively and caused histopathological changes suggestive of subacute to chronic mastitis during the experimental period. The results indicate that the tested M. canadense clinical isolate was virulent.

Studies on the immunogenic potential of plant-expressed cholera toxin B subunit

Nicotiana tabacum var. Samsun was transformed via Agrobacterium-mediated transformation with a gene encoding the cholera toxin B subunit (CTB) of Vibrio cholerae, modified to contain a sequence coding for an endoplasmic reticulum retention signal (SEKDEL), under the control of the cauliflower mosaic virus 35S promoter. Total protein from the transgenic leaf tissue was isolated and an aliquot containing 5 microg recombinant CTB was injected intradermally into Balb/c (H2K(d)) mice. CTB-specific serum IgG was detected in animals that had been administered plant-expressed or native purified CTB. A T-cell proliferation study using splenocytes and cytokine estimations in supernatants generated by in vitro stimulation of macrophages isolated from the immuno-primed animals was carried out. Inhibition of proliferation of T lymphocytes was observed in splenic T lymphocytes isolated from animals injected with either native or plant-expressed CTB. Macrophages isolated from mice immunised with native or plant-expressed CTB showed enhanced secretion of interleukin-10 but secretion of lipopolysaccharide-induced interleukin-12 and tumor necrosis factor alpha was inhibited. These studies suggest that plant-expressed protein behaved like native CTB with regards to effects on T-cell proliferation and cytokine levels, indicating the suitability of plant expression systems for the production of bacterial antigens, which could be used as edible vaccine. The transgene was found to be inherited in the progeny and was expressed to yield a pentameric form of CTB as evident by its interaction with G(M1) ganglioside.

Novel fluorophore for labelling of oligonucleotides

A novel fluorophore viz. 4-dansylamido-1,8-naphthalimido-N-pentanol has been designed, prepared and characterised. The comparative fluorescence has been studied in different solvents, solvent gradient, aqueous solutions of inorganic ions and buffers. This can be used for covalent tagging of oligonucleotides having potential application in Molecular Biology.

RETROSPECTIVE ANALYSIS OF BREAST CANCER CASES AND SURGICAL TREATMENT IN A PERIOD OF TEN YEARS

Retrospective analysis of 321 cases of breast cancer diagnosed in T. U Teaching Hospitalin a period of 10 years, from May, 1991 to April, 2000 was carried out. There were317 cases (98.8%) females and 4 cases males (1.2%). The youngest patient was 22year old female and oldest patient was 92 year old female. The most common agegroup according to frequency was in forties (34.6%) followed by in thirties (25.5 %).Mean duration of symptoms before coming to doctor was 8.3 months and mean size oftumor was 6 cm. Out of 317 females, 310(97.2%) were married and average numberof children was 3. Out of 289 cases diagnosed as malignancy with fine needle aspirationcytology (FNAC) 279 (96.5%) was also diagnosed as malignancy in biopsy and theremaining 10 cases as non malignant diseases were diagnosed as malignancy in biopsywith a false negative rate of 3.5%. The histological types of breast cancer cases wereInfiltrating Ductal Carcinoma 280 cases (87.2%), Medullary Carcinoma 11 cases(3.4%), Infiltrating Lobular Carcinoma 5 cases (1.6%), Mucinous Carcinoma 4 cases(1.2%), Sarcoma 4 cases (1.2%), Squamous Cell Carcinoma 4 cases (1.2%), PapillaryCarcinoma 3 cases (0.9%), Tubular Carcinoma 2 cases, Adenosquamous Carcinoma2 cases (0.6%), Intraductal Carcinoma 2 cases (0.6%) and Non-Hodgkins Lymphoma1 case. Out of 305 operated cases, the types of operation performed was ModifiedRadical Mastectomy in 208 cases (68 %) and palliative mastectomy in 72 cases (23.5%),only lumpectomy in 24 cases (7.9%) and others in 2 cases. Among 246 cases withavailable axillary lymph node biopsy, there was metastatic diseases in 146 cases (60%)of cases. The Breast cancer was diagnosed in advanced stages in 63% of cases. StageIIIA (24%), Stage IIIB (21.5%) and Stage IV (17.4%). Breast cancers were diagnosedin advanced stages in below 40 age group in 65 out of 90 cases (72.2 % ) comparedto137 out of 231 cases ( 59.3 % ) in above 40 age group.Key Words: Breast cancer, Advanced stage, FNAC, Surgery.

Recent Trends in Dealing with Inguinal Hernial Sac

High ligation of the hernial sac is a hallowed and time-honoured concept in inguinal hernia repair and it is considered essential for preventing recurrence. However, this concept has been contested in recent reports. We conducted a prospective study of 186 cases of inguinal hernia repair. In 92 cases the sac was ligated at the neck and excised, in 94 cases the sac was not ligated at all but either simply inverted or excised without ligation. The type of repair was Bassini's repair, Shouldice repair or Lichtenstein's repair. Degree of post-operative pain was significantly less in those cases where sac was not ligated. There were no cases of recurrence in either group at 3 years follow up. Ligation of sac in inguinal hernia surgery is not only unnecessary and time consuming but also leads to increased post-operation pain. Recurrence is unaffected by not ligating the sac.

Designing supramolecular structures from models of cyclic peptide scaffolds with heterocyclic constraints

Cyclic peptides containing oxazole and thiazole heterocycles have been examined for their capacity to be used as scaffolds in larger, more complex, protein-like structures. Both the macrocyclic scaffolds and the supramolecular structures derived therefrom have been visualised by molecular modelling techniques. These molecules are too symmetrical to examine structurally by NMR spectroscopy. The cyclic hexapeptide ([Aaa-Thz](3), [Aaa-Oxz](3)) and cyclic octapeptide ([Aaa-Thz](4), [Aaa-Oxz](4)) analogues are composed of dipeptide surrogates (Aaa: amino acid, Thz: thiazole, Oxz: oxazole) derived from intramolecular condensation of cysteine or serine/threonine side chains in dipeptides like Aaa-Cys, Aaa-Ser and Aaa-Thr. The five-membered heterocyclic rings, like thiazole, oxazole and reduced analogues like thiazoline, thiazolidine and oxazoline have profound influences on the structures and bioactivities of cyclic peptides derived therefrom. This work suggests that such constrained cyclic peptides can be used as scaffolds to create a range of novel protein-like supramolecular structures (e.g. cylinders, troughs, cones, multi-loop structures, helix bundles) that are comparable in size, shape and composition to bioactive surfaces of proteins. They may therefore represent interesting starting points for the design of novel artificial proteins and artificial enzymes.

War Wounds - Changing Concepts

The accepted standard treatment of war wounds through the last century has been debridement and delayed primary closure. However, recently, there has been a renewed Interest In primary closure of these wounds. 1481 war wounds were managed by the authors and out of 789 soft tissue injuries, 389 (47%) were closed primarily (group 1) after meticulous debridement and 220 (28%) underwent delayed primary closure (group 2). The infection rate in group 1 was 4.87% compared to 6.36% in group 2. The average hospital stay in group 1 was 15 days, significantly shorter by 10 days than in group 2. In the war zone both time and resources are at a premium and primary closure of selected wounds offers a better alternative to delayed primary closure.

Molecular theory of elastic constants of liquid crystals. III. Application to smectic phases with tilted orientational order

Using the density-functional formalism we derive an expression for the distortion free energy of systems with continuous broken symmetry and use it to derive an expression for the elastic constants of smectic phases in which the director is tilted with respect to the smectic layer normal. As in the previous papers of this series [Y. Singh, S. Singh, and K. Rajesh, Phys. Rev. A 45, 974 (1992); Y. Singh, K. Rajesh, V. J. Menon, and S. Singh, Phys. Rev. E 49, 501 (1994)], the expressions for the elastic constants are written in terms of order and structural parameters. The structural parameters involve the generalized spherical harmonic coefficients of the direct pair correlation function of an effective isotropic liquid. The density of this effective isotropic liquid depends on the nature and amount of ordering present in the system and is evaluated self-consistently. We estimate the value of elastic constants using reasonable guesses for the order and structural parameters.

Effect of defects on thermal denaturation of DNA oligomers

Effect of defects on the melting profile of short heterogeneous DNA chains is calculated using the Peyrard-Bishop Hamiltonian. On-site potential on a defect site is represented by a potential that has only a short-range repulsion and a flat part without well of the Morse potential. Stacking energy between two neigbouring pairs involving a defect site is also modified. The results are found to be in good agreement with the experiments.

SUBTOTAL THYROIDECTOMY IN THE MANAGEMENT OF GRAVE'S DISEASE

Treatment options for Grave's disease include radio-iodine ablation, which is the standard treatment in the USA, antithyroid drug therapy, which is popular in Japan, and surgery, which is commonly employed in Europe and India. There are very few reports about the outcome of surgery in Grave's disease in the Indian setting. Surgery for Grave's disease is an attractive option in under developed countries to cut short prolonged drug treatment, costly follow up and avoid the need for radio-isotope facilities for 1311 ablation. Aim of the present study was to assess the result of subtotal thyroidectomy in 32 cases of Grave's Disease referred for surgery by the endocrinologist in a teaching hospital. Patients were prepared for surgery with Lugol's iodine and propranalol. Subtotal thyroidectomy was performed by a standard technique, which included dissection and exposure of recurrent laryngeal nerves and parathyroid glands. Actual estimation of weight of the remnant gland was not part of the study. Duration of follow up ranged from 6 months to 4 years. 13 of 32 cases were males. Age ranged from 20 to 57 years. There was 1 death in the immediate post-operative period. There were no cases of permanent hypoparathyroidism or recurrent laryngeal nerve palsy. 1 patient developed temporary hypoparathyroidism. 1 patient developed recurrence of hyperthyroidism and 3 cases developed hypothyroidism all within 2 years of surgery. The study has demonstrated the safety and effectiveness of surgery for Grave's Disease in comparison to the reported high incidence of hypothyroidism following radio-iodine therapy and high recurrence rate after anti thyroid drug therapy.