Improved management can be achieved by introducing additional parameters in the syndromic diagnosis of nonviral sexually transmitted infections at low-resource settings.

BACKGROUND: The syndromic approach is a simple and affordable strategy for the management of sexually transmitted infections in countries with low-resource settings. However, because of the lack of specificity and accuracy, the risk of overuse and misuse of antibiotics is very high. Here, we proposed a more specific and accurate algorithm compared with the current algorithm used for syndromic case management of 3 common sexually transmitted pathogens and compared its precision with laboratory-based tests. OBJECTIVE: This study aimed to report a comparative account of the accuracy of existing syndromic case management guidelines followed in mainstream hospitals, for taking care of patients with nonviral sexually transmitted infections, concerning an approach involving an alternative algorithm formulated in our laboratory followed by polymerase chain reaction testing. STUDY DESIGN: This was an observational study that compared the data between 2 categories based on diagnostics accuracy and treatment. In category I, symptoms of infection were scored on the basis of the existing National AIDS Control Organization and National AIDS Control Programme guidelines, and patients were treated before testing by polymerase chain reaction. In category II, patients were recruited on the basis of the National AIDS Control Organization and National AIDS Control Programme guidelines with additional alternative syndromic case management parameters. All samples were tested by polymerase chain reaction for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis and clinically correlated before giving the treatment. RESULTS: In category I, among 646 women with symptomatic infection, only 46 (7.82%) tested positive by polymerase chain reaction assay for at least 1 of the pathogens, and 600 (92.87%) tested negative for infection by any of the 3 pathogens. The total estimated percentages of the overuse and misuse of antibiotics were 92.87% and 8.69%, respectively. Correct and complete treatment based on laboratory outcome compared with National AIDS Control Programme guidelines was 42 of 46 (91.30%). The estimated overuse of azithromycin and cefixime (Gray Kit) was 29.69%, the estimated overuse of a combination of doxycycline, cefixime, and metronidazole (Yellow Kit) was 29.87%, and the estimated overuse of a combination of doxycycline, cefixime, metronidazole, and azithromycin (Gray with Yellow Kit) was 11.45%. In category II, wherein patients were treated using an alternative syndromic approach and polymerase chain reaction diagnostics, 243 of 319 patients (76.15%) were infected with either of the pathogens (Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis), whereas 76 of 319 patients (23.82%) were negative for any of the 3 pathogens. Among 243 patients with infection, 99 of 243 (40.74%) were infected with a single pathogen, whereas 144 of 243 (59.20%) were coinfected. Of 144 coinfected patients, the percentage of Chlamydia trachomatis + Neisseria gonorrhoeae infection was the highest (51.38%), followed by coinfection with all 3 pathogens (30%). Coinfection with Chlamydia trachomatis + Trichomonas vaginalis was 9.72%, and coinfection with Neisseria gonorrhoeae + Trichomonas vaginalis was 9.03%. The estimated overuse of antibiotics was found to be 23.82% only. CONCLUSION: The proposed alternative strategies of syndromic case management can reduce the percentage of misuse and overuse of antibiotics from 92.87% to 23.82%. Moreover, syndromic case management alone was insufficient for disease management.

pH might play a role in regulating the function of paired amphipathic helices domains of human Sin3B by altering structure and thermodynamic stability.

Human Sin3B (hSin3B), a transcription regulator, is a scaffold protein that binds to different transcription factors and regulates transcription. It consists of six conserved domains that include four paired amphipathic helices (PAH 1-4), histone deacetylase interaction domain (HID), and highly conserved region (HCR). Interestingly, the PAH domains of hSin3B are significantly homologous to each other, yet each one interacts with a specific set of unique transcription factors. Though various partners interacting with hSin3B PAH domains have been characterized, there is no structural information available on the individual PAH domains of hSin3B. Here we characterize the structure and stability of different PAH domains of hSin3B at both nuclear and physiological pH values by using different optical probes. We found that the native state structure and stability of different PAH domains are different at nuclear pH where hSin3B performs its biological function. We also found that PAH2 and PAH3 behave differently at both nuclear and physiological pH in terms of native state structure and thermodynamic stability, while the structural identity of PAH1 remains unaltered at both pH values. The study indicates that the structural heterogeneity of different PAH domains might be responsible for having a unique set of interacting transcription factors.

A novel methodology for enhanced and consistent heterologous expression of unmodified human cytochrome P450 1B1 (CYP1B1).

Cytochrome P450 1B1 (CYP1B1) is a universal cancer marker and is implicated in many other disorders. Mutations in CYP1B1 are also associated with childhood blindness due to primary congenital glaucoma (PCG). To understand the CYP1B1 mediated etiopathology of PCG and pathomechanism of various cancers, it is important to carry out its functional studies. Heterologous expression of CYP1B1 in prokaryotes is imperative because bacteria yield a higher amount of heterologous proteins in lesser time and so the expressed protein is ideal for functional studies. In such expression system there is no interference by other eukaryotic proteins. But the story is not that simple as expression of heterologous CYP1B1 poses many technical difficulties. Investigators have employed various modifications/deletions of CYP N-terminus to improve CYP1B1 expression. However, the drawback of these studies is that it changes the original protein and, as a result, invalidates functional studies. The present study examines the role of various conditions and reagents in successful and consistent expression of sufficient quantities of unmodified/native human CYP1B1 in E. coli. We aimed at expressing CYP1B1 in various strains of E. coli and in the course developed a protocol that results in high expression of unmodified protein sufficient for functional/biophysical studies. We examined CYP1B1 expression with respect to different expression vectors, bacterial strains, types of culture media, time, Isopropyl ß-D-1-thiogalactopyranoside concentrations, temperatures, rotations per minute, conditioning reagents and the efficacy of a newly described technique called double colony selection. We report a protocol that is simple, easy and can be carried out in any laboratory without the requirement of a fermentor. Though employed for CYP1B1 expression, this protocol can ideally be used to express any eukaryotic membrane protein.

Interaction and structural modification of topoisomerase IIalpha by peptidyl prolyl isomerase, pin1: an in silico study.

The peptidyl prolyl isomerase (Pin1) that catalyzes the isomerization of peptide bonds involving proline and phosphorylated serine/threonine/tyrosine and alters the conformation and differential folding has been implicated in the regulation and function of phosphorylated proteins including mitotic and cell cycle proteins viz. Cdc25c, Bcl2, p53 etc. DNA topoisomerase IIalpha is one of the nuclear enzymes that maintain the DNA topology and regulates nuclear transactions like chromatin segregation and mitosis. In the present studies, we have carried out in-silico investigations on the possibilities of pin1 interaction with topo IIalpha and its functional regulation. We found ten potential pin1 interacting sites within topo IIalpha, which were part of loop and/or low complexity regions except helix at S802 within the catalytic domain. Proline directed phosphorylation was found to be possible at 1354, 1361, 1393 positions by cdk. Change in dihedral angle (omega) to 0 degree at all potential pin1 interacting sites at 575, 602, 802 and 950 for cis conformation of peptide bond introduced significant structural change with higher potential energy. All-cis-topo IIalpha structure reveals that potential pin1 sites come closer to each other, perhaps forming a motif, thereby suggesting cooperative phenomenon to maintain higher potential energy conformation. The bio-informatic analysis of topo IIalpha showed that multisite interaction of pin1 is possible at all the predicted sites. However, a strong possibility of pin1 interaction exist within c-terminal at 1213, 1247, 1354, 1361, 1393 sites, which may lead to either alterations in localization or modification in the activity and perhaps stability of the enzyme.

Comparison of an in-house PCR assay, direct fluorescence assay and the Roche AMPLICOR Chlamydia trachomatis kit for detection of C. trachomatis.

To improve the control of Chlamydia trachomatis infection in India, a rapid, specific and cost-effective method is much needed. We developed an in-house PCR assay by targeting a unique genomic sequence encoding a protein from the C. trachomatis phospholipase D endonuclease superfamily that produces an amplified fragment of 368 bp. The specificity of the primers was confirmed using genomic DNA from other sexually transmitted disease-causing and related micro-organisms and from humans. The assay was highly sensitive and could detect as low as 10 fg C. trachomatis DNA. Clinical evaluation of the in-house-developed PCR was carried out using 450 endocervical specimens that were divided in two groups. In group I (n=274), in-house PCR was evaluated against the direct fluorescence assay. The resolved sensitivity of the in-house PCR method was 97.22 % compared with 88 % for the direct fluorescent antibody assay. In group II (n=176), the in-house PCR was compared with the commercial Roche AMPLICOR MWP CT detection kit. The resolved sensitivity of the in-house PCR assay reported here was 93.1 % and the specificity was 97.46 %, making it a cost-effective alternative for routine diagnosis of genital infection by C. trachomatis. The method should facilitate early detection leading to better prevention and treatment of genital infection in India.