Biomechanical preparation in primary molars using manual and three NiTi instruments: a cone-beam-computed tomographic in vitro study.

PURPOSE: To evaluate nickel-titanium rotary systems, ProTaper Universal (PTU), ProTaper Next (PTN), self-adjusting file (SAF), and stainless steel hand K files in deciduous root canals in longitudinal and horizontal sections by three-dimensional reconstruction. Whether there was any difference in shaping ability, transportation, dentine removal, untouched canal surface area, and preparation time among the different groups when used in primary root canals. METHODS: Shaping and cleaning of canals in primary molars were done using the four systems, and CBCT and specialized software were used for scanning, image processing, three-dimensional reconstruction, and analysis of pre-operative and post-operative to evaluate the groups for their shaping properties, transportation, amount of dentine removal, untouched canal surface area, and preparation time in primary root canals. RESULTS: None of the groups reported stripping of canals or instrument failure. SAF demonstrated less removal of dentine as compared to other groups. Hand K files presented with high untouched canal surface area, while it was least with SAF. In addition, rotary files provided faster preparation than hand files, and among the rotary systems, PTN took least time for cleaning and shaping of canals. All the groups were similar in transportation at cervical and apical third. CONCLUSION: Under the conditions of this study, SAF seemed to result in more conservative and meticulous removal of dentine. This is desirable to preserve the integrity of thin-walled primary root canals. SAF also showed less untouched canal areas suggesting better contact with the primary canal walls. The rotary file groups required less clinical time which is important in paediatric treatments.

Study on Quality of IUD Services Provided by Trained Professionals at Teaching Institutes.

OBJECTIVE: Access the completeness in IUD services provided by trained professionals and find out the weak links. MATERIALS AND METHODS: Study was conducted on 100 IUD trained professionals of tertiary care hospital and nursing teaching institute. All were given questionnaire that was duly filled by them. Data obtained were analysed. Protocols of case selection, pre-insertion counselling, insertion process and follow-up were assessed. RESULTS: All the four criteria were assessed on score of ten. Study group could not get ten points under any of the set criteria. Average of 53% case selection, 31.4% pre-insertion counselling, 42.5% insertion protocols and 46.1% follow-up counselling criteria were observed by study group. Highest compliance of protocols was seen among postgraduate students. CONCLUSION: Although IUD training is given to all medical professionals and IUD facility is available up to subcentres but the study shows that completeness in services is still lacking. Ensuring ideal place for IUD insertion, proper case selection, use of specific instruments for insertion and observance of insertion protocols are very vital for the success of IUD.

Initial Stresses induced in Permanent Maxillary First Molar in Mixed Dentition under Normal Masticatory Forces: A Finite Element Study.

OBJECTIVE: The cross-arch space maintainers are used to prevent mesio-distal movement of teeth under physiologic forces, contrary to adult orthodontics where these are used as anchorage against orthodontic forces. Stresses in periodontal ligaments (PDL) are supposed to be different in pediatric dentistry and need to be studied. This study aimed to create mathematical model and calculated the initial stresses generated in the PDL and the behavior of movement in developing permanent maxillary first molar under masticatory forces using 3D finite element analyses (FEA). STUDY DESIGN: Data acquisition, image processing, geometric modeling followed by FE analyses was done under vertical load of 70N. The generated stress and tooth displacement were observed with or without primary second molar, mesial to permanent maxillary first molar. RESULTS: Masticatory forces resulted in insignificant initial PDL stresses and mesial displacement of permanent maxillary first molar in the intact arch. In the case of missing primary second molar, maximum stresses were on the palatal root and the tooth showed greater mesial displacement with mesio-palatal rotation. CONCLUSIONS: Any space maintainer preventing mesio-palatal rotation of permanent maxillary first molar, under physiologic masticatory loadings, may be inserted in case of multiple tooth loss.

Compliance assessment of cigarette and other tobacco products act in public places of Alwar district of Rajasthan.

BACKGROUND: The Government of India has taken various initiatives for tobacco control by enacting comprehensive tobacco control legislation (Cigarette and Other Tobacco Products Act [COTPA], 2003). OBJECTIVES: The aim of this study was to assess the level of compliance of Sections 4, 5, 6-a, and 6-b, and 7, 8, and 9 of COTPA with respect to public places, educational institutes, point of sale (PoS), and warning on packaging (COTPA) in public places of Alwar District of Rajasthan. METHODS: A cross-sectional observational study was conducted in 2014 in Alwar city and four blocks of the district. The study was done around 365 public places for observing the compliance of Section 4 of COTPA, 357 educational institutions for observing the compliance of Section 6-b of COTPA, and 357 tobacco retailers for observing the compliance of Sections 5 and 6-a of COTPA. RESULTS: The criteria for the evaluation (the core indicators) and decision criteria for a district to qualify for the "Smoke free" status include six parameters. From the total of 365 places visited, 90% places displayed the "No-smoking" signage and out of total 328 places, 99% were as per the COTPA specification. Alwar city, Ramgarh, Thanagaji, and Alwar rural block followed the compliance of Section 4. The PoS visited Alwar district displayed 93% (332) signage and all the displayed signage followed the COTPA compliance. In Alwar city, Thanagaji, Ramgarh, and Alwar rural block, the compliance of Section 6-a was above 90%. The compliance of Section 6-b was above 90% in Alwar city, Ramgarh, Thanagaji, and Alwar rural block. Ninety-three percent (332) of the PoS did not display tobacco advertisement in Alwar district, which is a positive sign of COTPA compliance. CONCLUSION: This finding suggest a high level of compliance of Section 4, Section 5, Section 6-a, and Section 6-b of COTPA at Alwar district.

Managing equipment for emergency obstetric care in rural hospitals.

In resource-poor countries, substantial sums of money from governments and international donors are used to purchase equipment for health facilities. WHO estimates that 50-80% of such equipment remains non-functional. This article is based on experience from various projects in developing countries in Asia and Africa. The key issues in the purchase, distribution, installation, management and maintenance of equipment for emergency obstetric care (EmOC) services are identified and discussed. Some positive examples are described to show how common equipment management problems are solved.

Self-sensitized photooxygenation of 3,4-dialkoxyfurans to vitamin C or its derivatives.

Self-sensitized photooxygenation of 3,4-dialkoxyfurans 3a-d with molecular oxygen and UV- or sunlight at room temperature gave vitamin C derivatives 2a-d in good to excellent yields. Furan 3c, having photodegradable protecting groups, was also photooxygenated to give L-ascorbic acid (1) in a "one-pot" reaction. Furthermore, a novel photolytic transformation was developed for deuteration of furan 3b at the C-2 position with D(2)O to give furan 3d in 95% yield. Toxicity of furans 3a-c and butenolides 2a-c against human embryonic cell, murine embryo fibroblasts, normal fibroblasts, HeLa, and Vero cell lines in the presence of oxygen and indirect solar light was found to be much less than those of the antipsoriasis drugs anthralin and 8-methoxypsoralen.

Design, synthesis, and biological evaluation of novel nucleoside and nucleotide analogues as agents against DNA viruses and/or retroviruses.

A novel strategy was developed for the synthesis of N(7)-purine acyclic nucleosides 9 and 14. The key step involved the reaction between [2-(p-methoxyphenyloxy)ethoxy]methyl chloride and N(9)-tritylated nucleobases 6 or 11 followed by concomitant self-detritylation. N(7)-Guanine acyclic nucleoside 9 exhibited antiviral activity, but was phosphorylated by both HSV and Vero cell thymidine kinases. Thus, it showed more potent cellular toxicity than acyclovir (2). N(7)-Adenine acyclic nucleoside 14 was found to be an excellent antiviral agent as well as a good inhibitor of calf mucosal adenosine deaminase. This inhibitory property allows for a greater expression of antiviral activity of antiviral agents, such as N(9)-adenine acyclic nucleoside 1 and ara-A (3). Compound 14 was phosphorylated neither by herpes simplex virus (HSV) thymidine kinase nor by Vero cell thymidine kinase, yet it enhanced the rate constant for the monophosphorylation of acyclovir (2) by HSV thymidine kinase. Consequently, the combination of acyclovir (2) and 14 exhibited greater antiviral activity than acyclovir alone. 7-[2-(Phosphonomethoxy)ethyl]adenine (20) was also synthesized. The key step involved the reaction of 9-(2-cyanoethyl)adenine (15) with methyl iodoacetate in the presence of lithium 2,2,6,6-tetramethylpiperidine in THF. Unlike 9-[2-(phosphonomethoxy)ethyl]adenine (PMEA, 4), the N(7)-isomer 20 was not phosphorylated effectively by 5-phosphoribosyl 1-pyrophosphate synthetase (PRPP synthetase). Thus, it did not exhibit pronounced antiviral activity. Dinucleotide 5'-monophosphate 24 and its butenolide ester 25 were also synthesized. Compound 24 showed substrate activity toward PRPP synthetase and exhibited notable activity against DNA viruses. The antiviral activity of the ester derivative 25 was found to be higher than that of the parent molecule 24. Dinucleotide 5'-monophosphate 24 is susceptible to degradation by snake venom and spleen phosphodiesterases. However, its respective butenolide ester derivative 25 was completely resistant to snake venom and spleen enzymes. Butenolide ester derivatives 28 and 29 were also synthesized and exhibited notable anti-DNA virus and anti-retrovirus activity in vitro. Compounds 2, 4, 9, 14, 20, 24, 25, and 28 were also evaluated for their inhibitory effect on HSV-1-induced mortality in NMRI mice. N(7)-adenine acyclic nucleoside 14 [LD(50) (intraperitoneal, ip) 950 mg/kg], nucleotide-containing butenolide 25 [LD(50) (ip) 675 mg/kg], and butenolide 28 [LD(50) (ip) 710 mg/kg] were found to be potent anti-HSV-1 agents in vivo. In addition, butenolide 28 efficiently decreased tumor formation induced by Moloney murine sarcoma virus (MSV) in NMRI mice while significantly increasing the survival time of MSV-infected mice.

The solution structure of [d(CGC)r(amamam)d(TTTGCG)]2.

The solution structure and hydration of a DNA.RNA hybrid chimeric duplex [d(CGC)r(amamam)d(TTTGCG)]2 in which the RNA adenines were substituted by 2'-O-methylated riboadenines was determined using two-dimensional NMR, simulated annealing, and restrained molecular dynamics. Only DNA residue 7T in the 2'-OMe-RNA.DNA junction adopted an O4'-endo sugar conformation, while the other DNA residues including 3C in the DNA.2'-OMe-RNA junction, adopted C1'-exo or C2'-endo conformations. The observed NOE intensity of 2'-O-methyl group to H1' proton of 4am at the DNA.2'-OMe-RNA junction is much weaker than those of 5am and 6am. The 2'-O-methyl group of 4am was found to orient towards the minor groove in the trans domain while the 2'-O-methyl groups of 5am and 6am were found to be in the gauche (+) domain. In contrast to the long-lived water molecules found close to the RNA adenine H2 and H1' protons and the methyl group of 7T in the RNA-DNA junction of [d(CGC)r(aaa)d(TTTGCG)]2, there were no long-lived water molecules found in [d(CGC)r(amamam)d(TTTGCG)]2. This is probably due to the hydrophobic enviroment created by the 2'-O-methylated riboadenines in the minor groove or due to the wider minor groove width in the middle of the structure. In addition, the 2'-O-methylation of riboadenines in pure chimeric duplex increses its melting temperature from 48.5 degrees C to 51.9 degrees C. The characteristic structural features and hydration patterns of this chimeric duplex provide a molecular basis for further therapeutic applications of DNA.RNA hybrid and chimeric duplexes with 2'-modified RNA residues.

Solution structure of the human BTK SH3 domain complexed with a proline-rich peptide from p120cbl.

X-linked agammaglobulinemia (XLA), an inherited disease, is caused by mutations in the Bruton's tyrosine kinase (BTK). The absence of functional BTK leads to failure of B cell differentiation which incapacitates antibody production in XLA patients leading to, sometimes lethal, bacterial infections. Point mutation in the BTK gene that leads to deletion of C-terminal 14 aa residues of BTK SH3 domain was found in one patient family. To understand the role of BTK in B cell development, we have determined the solution structure of BTK SH3 domain complexed with a proline-rich peptide from the protein product of c-cbl protooncogene (p120cbl). Like other SH3 domains, BTK SH3 domain consists of five beta-strands packed in two beta-sheets forming a beta-barrel-like structure. The rmsd calculated from the averaged coordinates for the BTK SH3 domain residues 218-271 and the p120cbl peptide residues 6-12 of the complex was 0.87 A (+/-0.16 A) for the backbone heavy atoms (N, C, and Calpha) and 1.64 A (+/-0.16 A) for all heavy atoms. Based on chemical shift changes and inter-molecular NOEs, we have found that the residues located in the RT loop, n-Src loop and helix-like loop between beta4 and beta5 of BTK SH3 domain are involved in ligand binding. We have also determined that the proline-rich peptide from p120cbl binds to BTK SH3 domain in a class I orientation. These results correlate well with our earlier observation that the truncated BTK SH3 domain (deletion of beta4, beta5 and the helix-like loop) exhibits weaker affinity for the p120cbl peptide. It is likely that the truncated SH3 domain fails to present to the ligand the crucial residues in the correct context and hence the weaker binding. These results delineate the importance of the C-terminus in the binding of SH3 domains and also indicate that improper folding and the altered binding behavior of mutant BTK SH3 domain likely lead to XLA.

Metastatic endophthalmitis in a patient with major burns: a rare complication.

A patient with 75 per cent of the body surface area burned developed metastatic endophthalmitis with orbital cellulitis leading to panophthalmitis in the right eye. In an estimated 1700 patients with burns treated in the same hospital over a period of 9 years (1984 to 1993), this is the first patient developing metastatic endophthalmitis. A possible pathological basis for the sequence of events is discussed.

Burns with pregnancy--a review of 25 cases.

We have treated 25 pregnant patients with burns over a period of 6 years (1986-91). During this period total admissions to the burn unit were 1260. There were 187 women of child-bearing age, with burns ranging between 15 and 100 per cent TBSA. We would like to emphasize that, with proper care, the prognosis of patients with burns who are pregnant is encouraging and is comparable to any other routine burn patient. Abortion was common in the first trimester of pregnancy. Septicaemia was the commonest cause of abortion. Fetal death is not always preceded by maternal death.

Pyogenic pericarditis in a patient with burns--a rare complication.

We report a patient with 60 per cent of the body surface area burned who developed pyogenic pericarditis which was treated successfully by open pericardial drain. In an estimated 1000 patients with burns treated in this hospital over a period of 5 years from 1984 to 1989, this is the first patient developing pyogenic pericarditis. A possible pathological basis for the sequence of events is discussed.

A second look at Steinach's second procedure: testiculoepididymal occlusion in man and dog.

After advocating vas occlusion as a biological method for rejuvenating aging males, Steinach had suggested that the effect might be more pronounced if the obstruction were placed proximal to the epididymis. This Steinach II procedure has now been studied in 15 dogs and five men. Occlusion was performed at the level of the vasa efferentia, avoiding any vascular trauma. Radiological visualization confirmed a perfect block. There were no untoward reactions, such as orchitis or hydrocele. In dogs, widespread degeneration in the seminiferous tubules was evident, and the total Leydig cell volume showed an increase from 0.7 to 1.0 ml/testis. The changes, however, were not significantly different from conventional vasectomy. In men, there were considerable preexisting senile changes, and the total Leydig cell volume was already as high as 2.8 ml/testis. These changes obscured any possible effect of Steinach II operation.

PIP: The placement of epididymal obstruction at vasectomy was investigated to see if such placement affects the biological rejuvenation of males. Whether placing the obstruction proximal to the epididymis (Steinach II) instead of beyond it (Steinach I) would make any difference in dogs and men was investigated. Steinach II was studied in 15 dogs and 5 men. Occlusion was performed at the level of the vasa efferentia, avoiding any vascular trauma. Radiological visualization confirmed a perfect block. There were no untoward reactions, such as orchitis or hydrocele. In dogs, widespread degeneration in the seminiferous tubules was evident; total Leydig cell volume showed an increase from .7-1 ml/testis. These changes were not significantly different from conventional vasectomy. In men, there were considerable preexisting senile changes; total Leydig cell volume was already as high as 2.8 ml/testis. Hence, any possible effect of the Steinach II procedure was obscured by these preexisting changes.

The total Leydig cell volume of the testis in some common mammals.

Total Leydig cell volume has been quantitatively determined by a histometric point-counting method in six common mammals, including man. Although the size of the testis has increased from 1.3 +/- 0.1 ml in the rat to 19.8 +/- 6.9 ml in the buffalo, the composition has remained fairly constant with the Leydig cells making up 9--16% of the testicular volume. In absolute terms, the Total Leydig Volume has increased progressively with body size, from 0.11 +/- 0.02 ml/testis in rat to 2.44 +/- 0.64 ml/testis in buffalo, the value for man being 2.21 +/- 0.40 ml/testis. The significance of these findings, from the point of view of the comparative physiology of male reproduction, has been discussed.