Prevalence and presentation of chronic venous disease in Pakistan: a multicentre study.

Our objective was to study the prevalence and clinical pattern of chronic venous disease (CVD) in the Pakistani population. This was a multicentre cross-sectional study in which 100 primary care physicians examined 3000 subjects. The study population was aged 18-95 years (mean ± SD = 39 ± 13.2) comprised 47.4% women and 52.6% men. The prevalence of CVD was 34.8%, being significantly higher (P < 0.04) among men (36.4%) than women (33.0%). The maximum prevalence was of C3 (36.7%), followed by C2 (15.8%). The most frequent symptom was pain in the legs (59.2%) followed by heavy legs (42.7%) and night cramps (34.4%). The prevalence of symptoms increased with age but was similarly distributed between men and women. Family history of CVD, blood clots in veins and lack of exercise were significant risk factors. The roles of age or gender as risk factors could not be established. In conclusion, the prevalence and presentation of CVD in Pakistan is similar to most other countries.

Integrin alpha2beta1 plays a critical role in osteoblast response to micron-scale surface structure and surface energy of titanium substrates.

Efforts to improve bone response to biomaterials have focused on ligands that bind alpha5beta1 integrins. However, antibodies to alpha5beta1 reduce osteoblast proliferation but do not affect differentiation when cells are grown on titanium (Ti). beta1-silencing blocks the differentiation stimulus of Ti microtopography, suggesting that other beta1 partners are important. Stably alpha2-silenced MG63 human osteoblast-like cells were used to test whether alpha2beta1 specifically mediates osteoblast response to Ti surface micron-scale structure and energy. WT and alpha2-silenced MG63 cells were cultured on tissue culture polystyrene (TCPS) and Ti disks with different surface microtopographies: machined pretreatment (PT) surfaces [mean peak to valley roughness (R(a)) < 0.02 microm], PT surfaces that were grit-blasted and acid-etched (SLA; R(a) = 4 microm), and SLA with high surface energy (modSLA). Alkaline phosphatase (ALP), alpha2 and beta1 mRNA, but not alpha5, alpha v, beta3, type-I collagen, or osteocalcin, increased on SLA and modSLA at 6 days. Alpha2 increased at 8 days on TCPS and PT, but remained unchanged on SLA and modSLA. Alpha2-protein was reduced 70% in alpha2-siRNA cells, whereas alpha5-mRNA and protein were unaffected. Alpha2-knockdown blocked surface-dependent increases in beta1 and osteocalcin and decreases in cell number and increases in ALP and local factors typical of MG63 cells grown on SLA and modSLA [e.g., prostaglandin E(2), osteoprotegerin, latent and active TGF-beta1, and stimulatory effects of 1alpha,25(OH)(2)D(3) on these parameters]. This finding indicates that alpha2beta1 signaling is required for osteoblastic differentiation caused by Ti microstructure and surface energy, suggesting that conclusions based on cell behavior on TCPS are not predictive of behavior on other substrates or the mechanisms involved.

Pulsed electromagnetic fields enhance BMP-2 dependent osteoblastic differentiation of human mesenchymal stem cells.

Mesenchymal stem cells (MSCs) express an osteoblastic phenotype when treated with BMP-2, and BMP-2 is used clinically to induce bone formation although high doses are required. Pulsed electromagnetic fields (PEMF) also promote osteogenesis in vivo, in part through direct action on osteoblasts. We tested the hypothesis that PEMF enhances osteogenesis of MSCs in the presence of an inductive stimulus like BMP-2. Confluent cultures of human MSCs were grown on calcium phosphate disks and were treated with osteogenic media (OM), OM containing 40 ng/mL rhBMP-2, OM + PEMF (8 h/day), or OM + BMP-2 + PEMF. MSCs demonstrated minor increases in alkaline phosphatase (ALP) during 24 days in culture and no change in osteocalcin. OM increased ALP and osteocalcin by day 6, but PEMF had no additional effect at any time. BMP-2 was stimulatory over OM, and PEMF + BMP-2 synergistically increased ALP and osteocalcin. PEMF also enhanced the effects of BMP-2 on PGE2, latent and active TGF-beta1, and osteoprotegerin. Effects of PEMF on BMP-2-treated cells were greatest at days 12 to 20. These results demonstrate that PEMF enhances osteogenic effects of BMP-2 on MSCs cultured on calcium phosphate substrates, suggesting that PEMF will improve MSC response to BMP-2 in vivo in a bone environment.

The preparation of a highly specific antiserum for the immunoassay of pregnanediol 3 alpha-glucuronide.

Antisera for the radioimmunoassay of pregnanediol glucuronide have in the past been raised against immunogens in which the carboxyl group of the glucuronide has been attached to the protein. Such antisera do not discriminate well between the glucuronide and the unconjugated steroid. In order to increase this discrimination we have synthesized an immunogen in which the triacetoxy methyl ester of pregnanediol glucuronide is attached to the protein by a 6 beta-hemisuccinoxy bridge. This immunogen was then deprotected to expose the glucuronide. In one group of rabbits deprotection was achieved in vivo simply by injecting the immunogen. In a second group the immunogen was selectively hydrolysed prior to immunization. The antisera raised against these immunogens possessed high affinity and discriminated well between the free steroid and the steroid glucuronide.

An improved synthesis of 6beta-hydroxy-5beta-pregnane-3,20-dione.

6beta-Hydroxy-5beta-pregnane-3,20-dione, formerly prepared by hydroboration method, has been obtained in greatly improved yield by a simpler irradiation-hydrogenation procedure.

Transstadial transmission of Theileria annulata through common ixodid ticks infesting Indian cattle.

Transstadial transmission of Theileria annulata with Hyalomma anatolicum anatolicum, H. dromedarii and H. marginatum isaaci, and Haemaphysalis bispinosa, Rhipicephalus haemaphysaloides haemaphysaloides and Boophilus microplus was determined. It was found that the infection was successfully transmitted by H. a. anatolicum from larva to nymph and nymph to adult in all attempts. When larvae were fed on an infected calf the succeeding adults transmitted the infection when the intervening nymphs fed on a rabbit (non-susceptible host) but not when fed on a calf (susceptible host). Infective adult ticks transmitted the parasite during the first 24 h of feeding on a calf. When the feeding was interrupted after 24 h, and the tick transferred to another calf, the infection was transmitted to the latter as well. H. dromedarii successfully transmitted the infection from larva to nymph and from nymph to adult. Larvae of H. marginatum isaaci did not feed on calves but the infection was successfully transmitted from nymph to adult. Haemaphysalis bispinosa, Rhipicephalus h. haemaphysaloides and Boophilus microplus did not transmit Th. annulata from larva to nymph to adult.

Studies on the development of Theileria annulata Dschunskowsky and Luhs, 1904 in the tick--Hyalomma anatolicum anatolicum Koch, 1844.

The endogenous development of Theileria annulata in the vector tick--Hyalomma anatolicum anatolicum has been described. Parasites within and outside the erythrocytes were seen in the gut contents of larvae and nymphs immediately after their removal from the infected cattle but not after 24 hours. Two bodies resembling the intra-erythrocytic stage of the parasite, lying close to each other were seen near the gut epithelium of a larva on the 4th day of its dropping off the infected host. Neither multiplication nor union of the parasite resulting in zygote formation in the gut of the tick, was noticed. Next stage of the parasite was seen in the salivary glands of nymphs and adults. The pre-infective stage characterized by indistinct chromatin dots (nuclei) surrounded with cytoplasm was seen in alveolar cells of the salivary glands of nymphs and adult ticks from the first to the third day of their feeding of the host. This stage progressed to the infective stage consisting of distinct chromatin particles (the infective particles) surrounded with cytoplasm in the salivary glands of nymphs and adult ticks after the second and first day, respectively of feeding on the host. The infective particles were also seen within ducts of the salivary glands.