Combining Platelet-Rich Plasma Instillation With Core Decompression Improves Functional Outcome and Delays Progression in Early-Stage Avascular Necrosis of Femoral Head: a 4.5- to 6-Year Prospective Randomized Comparative Study

BACKGROUND

Avascular necrosis of femoral head is a debilitating disease frequently progressing to femoral head collapse and joint destruction. The efficacy of core decompression (CD) remains controversial.

METHODS

About 40 consecutive age-matched and gender-matched patients (53 hips) were randomized into 2 groups by computer-generated algorithm table in a prospective randomized double-blinded comparative study. Group A (platelet-rich plasma [PRP] with CD) included 19 patients (25 hips), and group B (CD only) included 21 patients (28 hips). Postoperative Harris Hip Score and magnetic resonance imaging to quantify the necrotic area by using modified Kerboul angle were done and evaluated. Mean follow-up was 64.3 months (range, 54-72) and 63.7 months (range, 56-72) in groups A and B, respectively.

RESULTS

There was statistically significant difference between PRP and control groups in pain score (P = .00), functional score (P = .02), and Harris Hip Score (P = .00) at final follow-up. There was no progression in stage 1 disease. Stage 2 disease showed 24% progression in group A and 43% progression in group B. The difference was statistically significant (P = .025). Survivorship from femoral head collapse, any procedure, and total hip arthroplasty was 84%/68% (P = .00), 76%/57% (P = .02), and 92%/78% (P = .01) in 2 groups, which was statistically significant.

CONCLUSION

PRP use after CD provides significant pain relief, better midterm functional outcome, retards the progression, and enhances the survivorship free from reoperation for hip arthroplasty and femoral head collapse in early stages of avascular necrosis of hip than CD alone.

Tele-evidence: A videoconferencing tool as a viable alternative to physical appearance of doctors for the judicial summons

Introduction:

The role of physicians often extends beyond provision of direct patient care and includes appearance in courts as professional or expert witnesses to give their testimony in various legal cases. This often consumes precious time and resources of the doctors and the hospitals. This study was taken up to evaluate the present system of the physical appearance of the doctors to various courts and compare it with the videoconferencing mode of giving testimony (tele-evidence).

Materials and Methods:

Available records of summons and vehicles used were analyzed to calculate the cost involved and man-hours consumed in honoring the court summons. Telemedicine facility, available in our institute, was used for conducting tele-evidence with selected courts of the two states as a pilot, which was later expanded. A survey was also done to assess the experience of the physicians with physical appearance and videoconferencing using structured questionnaire after approval from the Institute's Ethics Committee. Likert scale of 0–10 points was used to measure satisfaction.

Results:

There was 43% drop in the monthly mileage of vehicles, 49% reduction in the fuel cost per month, and 28% savings in terms of time consumed for court duties. Satisfaction score for parameters of time consumed, physical strain, mental strain, communication with Honorable Judges, and overall experience was 87% through tele-evidence as compared to 31% with physical appearance.

Conclusion:

Tele-evidence is an acceptable and implementable mode of testifying and has led to tremendous resource savings in our tertiary care setting. The model needs to be replicated for deliverance of justice and is in consonance with Government's push toward Digital India.

Topical vs Intravenous Tranexamic Acid in Reducing Blood Loss After Bilateral Total Knee Arthroplasty: A Prospective Study

BACKGROUND

Total knee arthroplasty (TKA) results in substantial postoperative blood loss with increased morbidity. Despite various studies proving the efficacy of tranexamic acid (TXA), no consensus exists on the routes of administration.

METHODS

Seventy consecutive patients with knee arthritis undergoing simultaneous bilateral TKA, who were eligible and fulfilled the criteria, were taken up for this study. They were randomly allocated by a computer-generated random number table, either to receive intravenous TXA (IVTXA; group 1) or topical TXA (TTXA; group 2) in a prospective, double-blinded study. The primary outcome measures were total blood loss and total drain output. The secondary outcome measures were number of blood units transfused and clinical and functional outcomes as evaluated by the Knee Society Score, Western Ontario and McMaster Universities Arthritis Index score, visual analog score, and wound score.

RESULTS

Both groups were similar in age, sex, and body mass index, and no statistical significance was observed. There was statistically significant difference between IVTXA and TTXA groups in mean postoperative total blood loss (P < .001), postoperative hemoglobin (P < .001) with a higher drop of hemoglobin in the former, total drain output (P < .001), and allogeneic blood transfusion (P < .001). No complication was observed in either group. Significant difference was observed in the Western Ontario and McMaster Universities Arthritis Index score at 12 weeks and 6 months (P = .015 and .007) and Knee Society Score at 6 and 12 months (P = .050 and .045, respectively). However, no significant difference was found at 6 weeks.

CONCLUSION

TTXA is better than IVTXA in reducing blood loss and clinical outcome after simultaneous bilateral TKA.

Femoral head fracture without hip dislocation

Femoral head fractures without dislocation or subluxation are extremely rare injuries. We report a neglected case of isolated comminuted fracture of femoral head without hip dislocation or subluxation of one year duration in a 36-year-old patient who sustained a high energy trauma due to road traffic accident. He presented with painful right hip and inability to bear full weight on right lower limb with Harris hip score of 39. He received cementless total hip replacement. At latest follow-up of 2.3 years, functional outcome was excellent with Harris hip score of 95. Such isolated injuries have been described only once in the literature and have not been classified till now. The purpose of this report is to highlight the extreme rarity, possible mechanism involved and a novel classification system to classify such injuries.

Predictors of posterior cruciate ligament degeneration in osteoarthritic knees

PURPOSE

To evaluate the tibial articular cartilage and histology of the posterior cruciate ligament (PCL) in osteoarthritic knees so as to determine predictors of PCL degeneration.

METHODS

23 advanced osteoarthritic knees (mean patient age, 61 years) treated with total knee arthroplasty (TKA) were prospectively studied. The Knee Society Score was assessed. Osteoarthritic changes on radiographs were graded as mild, moderate, or severe. Tibial articular cartilage erosion was assessed. The appearance of both cruciate ligaments was classified as normal, abnormal (thinner and sclerotic), or ruptured. Both ligaments were examined histologically for degenerative changes. Each degenerative change of the PCL was graded by 2 histopathologists twice separately. Higher scores indicated more severe degeneration.

RESULTS

Of the 23 knees, the gross appearance of the anterior cruciate ligaments (ACLs) was normal in 6, abnormal in 11, and ruptured in 6. Histologically, the PCLs were normal in 4, minimally degenerated in 2, mildly in 8, moderately in 5, and severely in 4. The predominant degenerative change was the presence of loose fibrous tissue. ACL appearance correlated positively with PCL degeneration (r=0.883, p=0.001). The mean Knee Society Score was 24 (range, 0-43), and the mean function score was 30 (range, 5-55). PCL degeneration correlated positively with the Knee Society Score (r=0.565, p=0.02) but not with the function score (r=0.061, p=0.447). Anteroposterior instability correlated positively with PCL degeneration (r=0.691, p=0.01). Erosion in the lateral tibiofemoral compartment and ACL insufficiency were indicators of PCL degeneration (despite a normal appearance). Inter-observer reliability and intra-observer reproducibility were 0.82 and 0.87, respectively.

CONCLUSION

The Knee Society Score, anteroposterior instability, ACL appearance, and erosion in the lateral tibiofemoral compartment are predictors of PCL degeneration and can help decide on the optimal type of TKA implant (PCL-retaining vs. PCL-sacrificing design).

Anatomical variation in formation of brachial plexus and its branching

Variant brachial plexus formation with two trunks and two cords is uncommon and has clinical implications as it may result in failure of regional brachial or axillary block. During routine anatomical dissection, unilateral variation in the formation of brachial plexus accompanied by unusual positional relationship with axillary artery was discovered in the left upper extremity of a 52-year-old Indian male cadaver. Brachial plexus showed two trunks formed by ventral rami of C5, C6 and C7, C8, T1 spinal nerves, respectively, which first split and then reunited in an unusual manner to form two cords: posterior and lateral instead of three. Medial cord was absent. The branching pattern of the brachial plexus also showed important variations. Second part of axillary artery was found lying inferomedial to brachial plexus instead of passing between medial and lateral cords. Transverse cervical artery was found to be coursing between two trunks instead of passing superficial to brachial plexus. Median nerve was observed to be formed from a single root, instead of usual two roots. Embryologically, this rare variation may be due to the development of axillary artery from ninth segmental artery instead of usual seventh cervical intersegmental artery. Such rare variation is clinically important as this knowledge may help the anesthesiologists and the surgeons to avoid any inadvertent damage to nerves and axillary artery during blocks and surgical interventions.

Anatomic consideration of caudal epidural space: a cadaver study

The knowledge of sacral hiatus anatomy is imperative in clinical situations requiring caudal epidural block for various diagnostic and therapeutic procedures of the lumbosacral spine to avoid failure and dural injury. In this study, a detailed anatomic study of the sacral region was carried out on 49 male adult Indian cadavers. Dorsal surface of sacral region was dissected to study sacral cornua, sacral hiatus, and the dimensions of triangle formed by the right and left posterosuperior iliac spines with apex of the hiatus. Midsagittal sections were subjected for various anatomical measurements. The angle of needle insertion and the depth of caudal space were noted. Cornu was not palpable bilaterally in 7 (14.3%) and palpable unilaterally in 12 (24.5%) specimens. Mean (standard deviation) distance between apex of hiatus and coccyx tip was 57.5 (8.7) mm and length of sacrococcygeal ligament was 34.2 (7.4) mm. The dimensions of the triangle were found to be interchangeable in 25 cadavers. Once the needle is introduced into the canal after penetrating the sacrococcygeal ligament, it should not be advanced >5 mm to prevent dural puncture. The level of maximum curvature of sacrum was S3 in 34 (69.4%) of cases. The dural sac was found to terminate at S2 in 41 (83.6%). The mean (SD) angle of depression of the needle was 65.7 (5.5) (range 58-78). The measurements described for the identification of the sacral hiatus, optimal angle of depression, and depth of the needle may improve the safety and reliability of a caudal epidural block.

Folding mirror schlieren diffraction interferometer

We demonstrate the use of a mirror as a viewing diaphragm to generate a built-in diffracted reference beam in schlieren diffraction interferometry (SDI). The use of a mirror edge as a diffracting element instead of a conventional knife edge considerably enhances the contrast of the schlieren pattern, and it is shown to be equal to that of a phase knife edge. This increase in contrast is due to the fact that the otherwise unutilized diffracted beam in SDI is recombined in the described folding mirror geometry.

Hybrid external fixation in periarticular tibial fractures. Good final outcome in 56 patients

Out of 65 patients with periarticular fractures of the tibia treated by use of hybrid external fixation (a combination of indigenously manufactured version of ring and AO tubular fixator) from February 1997 to October 2003, 56 cases were taken up for this study with a minimum follow-up of 12 months. The injury was due to a high-velocity motor vehicle accident in 49 and a fall in 7 patients. Thirty five were tibial plateau fractures and 21 were distal tibial plafond fractures. Forty eight were compound fractures and eight were closed. They were treated by debridement (48 compound) and hybrid external fixator (n = 56). All the patients were assessed clinically and radiographically for an average follow-up of 42.5 months (range: 12 to 67). In tibial plateau fractures (n = 35), the final outcome was good to excellent in 30, fair in 2 and poor in 3. In tibial plafond fractures (n = 21), results were good to excellent in 16, fair in 3 and poor in 2. We recommend the use of hybrid external fixator for periarticular tibial fractures occurring due to high-energy trauma. In addition, rates of complications as seen with other modalities of fixation are greatly reduced. It facilitates adequate care of associated soft tissue injuries.

Brown-Vialetto-Van Laere syndrome; variability in age at onset and disease progression highlighting the phenotypic overlap with Fazio-Londe disease

We report four siblings showing features of a pontobulbar palsy, a mixed spinal and upper motor neuropathy and variable deafness. The observation of affected males and females born to consanguineous first cousin parents suggests autosomal recessive inheritance. Two children presented in the first 16 months of life with stridor and died of respiratory failure by the age of 2 years. Hearing loss was not apparent in these infants. In contrast, 2 further siblings developed a bulbar palsy in their sixth year followed by the onset of deafness and features of an anterior horn neuropathy with corticospinal tract involvement. They exhibited a relatively slow but relentless decline over a period of several years. These cases highlight the phenotypic overlap of Brown-Vialetto-Van Laere syndrome with Fazio-Londe disease. Rather than representing two separate disorders, our findings suggest the possibility of a single disease entity which may usefully be considered a form of juvenile amyotrophic lateral sclerosis.

Open reduction and internal fixation of volar Barton's fractures: a prospective study

PURPOSE

To assess the functional and clinical outcomes of open reduction with internal fixation in the treatment of Barton's fracture of the wrist.

METHODS

From January 1997 to July 2003, a total of 19 cases of volar Barton's fracture were operated on by open reduction and internal fixation at the Nehru Hospital, Chandigarh, India. Records of 16 cases were available for study. Special care was taken during surgery to achieve articular congruity. The injury was caused by motor vehicle accidents in 13 cases and by a fall in 3. All cases were type-B3 fractures: 10 were of the B3.3 subtype, 4 of the B3.2 subtype, and 2 of the B3.1 subtype. Most (12) cases were operated on within one week of injury, 3 in one to 2 weeks, and one in 2 to 3 weeks.

RESULTS

All patients were assessed clinically and radiographically after a mean follow-up duration of 32.4 months (range, 12.0-65.0 months). Fractures healed after 7.0 to 10.0 weeks (mean, 8.8 weeks). Results of evaluations according to functional criteria were excellent in 9 cases, good in 5, and fair in 2. Radiocarpal osteoarthrosis developed secondary to trauma in 2 cases. There was no involvement of the median nerve in any of the 16 cases.

CONCLUSION

Open reduction and internal fixation of volar Barton's fracture can restore articular congruity and result in good to excellent function.

Insular carcinoma of thyroid--a case report

Insular carcinoma of thyroid (ICT) is a rare tumor, which accounts for 4-6% of thyroid malignancies. ICT arising from follicular cells of thyroid shows a characteristic insular growth pattern characterized by solid nests of tumor cells separated by vessels. A 52-year-old female presented with a huge swelling in midline of the neck with retrosternal extension. The patient was euthyroid. Near total thyroidectomy was done. Grossly, the tumour was involving both the lobes and isthmus of thyroid. Microscopic examination revealed features of insular carcinoma. On immunohistochemistry, tumour cells were positive for thyroglobulin and negative for calcitonin.

Shape, measurements and weight of the thyroid gland in northwest Indians

The shape of the thyroid gland, its extension as the pyramidal lobe (PL) and attachments of the levator glandulae thyroideae (LGT) were studied in 410 male and 160 female adults from the Chandigarh zone in northwest India during medicolegal autopsies performed in the department. Whereas the measurements of the gland were recorded in 210 subjects, the weights were taken only in 160 instances. The shapes of the glands were: lateral lobes (LL) with isthmus (50.2%), horseshoe-shaped gland (36.8%), gland with separate lobes (7.9%) and irregularly shaped gland (5.1%). No sexual dimorphism was seen in the incidence of various shapes of the gland. The incidence of the PL and LGT was 28.9% and 19.5%, respectively. Neither a PL nor LGT was present in irregularly shaped glands. The mean weight of the gland was 15.01+/-7.69 g in males and 13.16+/-5.64 g in females. Sexual and age-wise differences in weights were found to be statistically insignificant. A survey involving 152 subjects in 2 villages in Chandigarh showed that it is an iodine sufficient zone. The size and weight of thyroid glands in adults of the two genders were found to be smaller than in western Caucasian and Japanese subjects.

Giant combined dermatofibroma with satellitosis

An unusual giant combined dermatofibroma is reported in a 34-year-old man who presented with skin-coloured swellings on the medial aspect of the left scapula. The plaque was well defined, reddish-brown and 25-30 cm in diameter. It was also tender and indurated. Several similar smaller lesions (satellites) were present around the plaque. Light microscopy of an incisional biopsy from the main lesion showed architectural features of a deep penetrating type of dermatofibroma, with xanthomatous aggregates, myxoid changes and probable myofibroblastic differentiation. Our case represents an extraordinary example of giant combined dermatofibroma with satellitosis. Despite its benign nature, a wide excision is contemplated because of its unsightly appearance and physical discomfort.

A serological study of human toxocariasis in north India

BACKGROUND

Human toxocariasis owing to lodgement of the larvae of Toxocara canis in different organs can result in serious clinical syndromes such as visceral larva migrans or ocular larva migrans. Detection of an antibody response to Toxocara canis excretory-secretory (TES) antigen in serum samples is sensitive and specific for diagnosis and epidemiological surveys. To assess the extent of this problem in northern India, we tested the antibody response to the TES antigen by ELISA technique in subjects residing in a rural area near Chandigarh and in patients attending Nehru hospital, Chandigarh and clinically suspected to have toxocariasis.

METHODS

Serum samples were collected from 94 randomly selected subjects, residents of Kheri village, Ambala district, Haryana; 30 patients clinically suspected to have toxocariasis attending Nehru hospital, Chandigarh; 25 control patients and 15 normal healthy individuals. These were subjected to ELISA technique for detection of an antibody response to TES antigen usinga commercial kit (LMD Laboratories Inc. Ca. USA). All the samples were tested in duplicate and positive samples were tested by a different kit (Melotec Biotechnology, Spain).

RESULTS

Of the 94 subjects residing in Kheri village and 30 clinically suspected toxocariasis patients, 6 (6.4%) and 7 (23.3%), respectively, were seropositive for anti-Toxocara antibody response. A history of pica and/or contact with puppies could not be obtained from all the subjects/patients, hence the exact mode of transmission could not be ascertained. However, 3 (3.2%), 2 (2.13%) and 1 (1.06%) seropositive subjects in Kheri village were in the age groups of 1-10, 11-20 and 21-30 years, respectively, while 4 (13.33%) and 3 (10%) seropositive patients who attended Nehru hospital, Chandigarh were in the age groups of 1-10 and 21-30 years, respectively. None of the control patients/healthy individuals were seropositive.

CONCLUSION

A positive antibody response to TES antigen in 6.4% subjects residing in a rural area near Chandigarh and in 23.3% of patients clinically suspected to have toxocariasis indicates that human toxocariasis may be endemic in certain regions of northern India. A detailed epidemiological study is needed to determine the extent of this problem.

Animal bite management practices: a survey of health care providers in a community development block of Haryana

It is seen that outcome of animal bites is influenced by various factors including the treatment procedures practiced by health care providers (HCPs). A cross sectional study of health care providers was conducted during May 2000 in PHC Kurali and Naraingarh town of community development block Naraingarh in district Ambala, Haryana. A total of forty-four HCPs were interviewed at their health facility. They were asked about the qualification and number of years in practice. Health care providers were assessed for their knowledge regarding history taking, immediate management of animal bite, post bite anti-rabies treatment, follow up advice and availability of vaccines. Pre-exposure prophylaxis was known to 18.8% of HCPs. Fifty-nine per cent of HCPs were confident in managing dog bites and 93.1% knew about tissue culture vaccine. Vaccine cost was the commonest barrier (38.8%) in the management of animal bites. This study shows a gross difference between awareness and actual practice of management of animal bites.

Structure of the catalytic core of S. cerevisiae DNA polymerase eta: implications for translesion DNA synthesis

DNA polymerase eta is unique among eukaryotic polymerases in its proficient ability to replicate through a variety of distorting DNA lesions. We report here the crystal structure of the catalytic core of S. cerevisiae DNA polymerase eta, determined at 2.25A resolution. The structure reveals a novel polydactyl right hand-shaped molecule with a unique polymerase-associated domain. We identify the catalytic residues and show that the fingers and thumb domains are unusually small and stubby. In particular, the unexpected absence of helices "O" and "O1" in the fingers domain suggests that openness of the active site is the critical feature which enables DNA polymerase eta to replicate through DNA lesions such as a UV-induced cis-syn thymine-thymine dimer.

Comparative study of various endoscopes for pulsed digital holographic interferometry

A comparison of several endoscopes as object image carriers in pulsed digital holography is presented. Three multicore flexible fiber endoscopes of different spatial resolution and one rigid endoscope are investigated. The four endoscopes are integrated in a setup for the recording of digital holograms on a CCD camera. A double-pulsed ruby laser is used as the light source. A spatial carrier is introduced by an off-axis reference beam, which permits quantitative evaluation of the phase difference between two holograms recorded with a short time separation (5-600 micros). From reported studies it may be inferred that the quality of the phase maps so derived from digital holographic interferometry has a strong correlation to the spatial resolution of the multicore fiber used in these endoscopes. With the endoscopic technique combined with pulsed digital holography a number of useful applications (in areas such as medical endoscopy, micromechanics, and microelectronics) are envisaged for which access to the objects of interest is otherwise difficult.

E-commerce in healthcare: changing the traditional landscape

The healthcare industry, with more than one trillion dollars in revenue, accounts for about one-seventh of the U.S. economy. A significant portion of this revenue is lost to escalating healthcare system costs. This article examines the shortcomings of the traditional healthcare delivery system in terms of information flow, communication standards, case collections, and IT spending. It makes the case that e-commerce has the ability to transact some healthcare business more efficiently and cost-effectively. With the Internet as a delivery platform, several models offer improvement over the status quo.

FokI requires two specific DNA sites for cleavage

FokI is a bipartite restriction endonuclease that recognizes a non-palindromic DNA sequence, and then makes double-stranded cuts outside of that sequence to leave a 5' overhang. Earlier kinetic and crystallographic studies suggested that FokI might function as a dimer. Here, we show, using dynamic light-scattering, gel-filtration and analytical ultracentrifugation, that FokI dimerizes only in the presence of divalent metal ions. Furthermore, analysis of the DNA-bound complex reveals that two copies of the recognition sequence are incorporated into the dimeric complex and that formation of this complex is essential for full activation of cleavage. These results have broad implications for the mechanism by which monomeric type II endonucleases achieve high fidelity.

Structure of Pumilio reveals similarity between RNA and peptide binding motifs

Translation regulation plays an essential role in the differentiation and development of animal cells. One well-studied case is the control of hunchback mRNA during early Drosophila embryogenesis by the trans-acting factors Pumilio, Nanos, and Brain Tumor. We report here a crystal structure of the critical region of Pumilio, the Puf domain, that organizes a multivalent repression complex on the 3' untranslated region of hunchback mRNA. The structure reveals an extended, rainbow shaped molecule, with tandem helical repeats that bear unexpected resemblance to the armadillo repeats in beta-catenin and the HEAT repeats in protein phosphatase 2A. Based on the structure and genetic experiments, we identify putative interaction surfaces for hunchback mRNA and the cofactors Nanos and Brain Tumor. This analysis suggests that similar features in helical repeat proteins are used to bind extended peptides and RNA.

Amino-terminal domain exchange redirects origin-specific interactions of adeno-associated virus rep78 in vitro

The unique ability of adeno-associated virus type 2 (AAV) to site-specifically integrate its genome into a defined sequence on human chromosome 19 (AAVS1) makes it of particular interest for use in targeted gene delivery. The objective underlying this study is to provide evidence for the feasibility of retargeting site-specific integration into selected loci within the human genome. Current models postulate that AAV DNA integration is initiated through the interactions of the products of a single viral open reading frame, REP, with sequences present in AAVS1 that resemble the minimal origin for AAV DNA replication. Here, we present a cell-free system designed to dissect the Rep functions required to target site-specific integration using functional chimeric Rep proteins derived from AAV Rep78 and Rep1 of the closely related goose parvovirus. We show that amino-terminal domain exchange efficiently redirects the specificity of Rep to the minimal origin of DNA replication. Furthermore, we establish that the amino-terminal 208 amino acids of Rep78/68 constitute a catalytic domain of Rep sufficient to mediate site-specific endonuclease activity.

BglII and MunI: what a difference a base makes

Restriction endonucleases are resilient to alterations in their DNA-binding specificities. Structures of the BglII and MunI endonucleases bound to their palindromic DNA sites, which differ by only their outer base pairs from the recognition sequences of BamHI and EcoRI, respectively, have recently been determined. A comparison of these complexes reveals surprising differences and similarities in structure, and provides a basis for understanding the immutability of restriction endonucleases.

Structure of free BglII reveals an unprecedented scissor-like motion for opening an endonuclease

Restriction endonuclease BglII completely encircles its target DNA, making contacts to both the major and minor grooves. To allow the DNA to enter and leave the binding cleft, the enzyme dimer has to rearrange. To understand how this occurs, we have solved the structure of the free enzyme at 2.3 A resolution, as a complement to our earlier work on the BglII-DNA complex. Unexpectedly, the enzyme opens by a dramatic 'scissor-like' motion, accompanied by a complete rearrangement of the alpha-helices at the dimer interface. Moreover, within each monomer, a set of residues--a 'lever'--lowers or raises to alternately sequester or expose the active site residues. Such an extreme difference in free versus complexed structures has not been reported for other restriction endonucleases. This elegant mechanism for capturing DNA may extend to other enzymes that encircle DNA.

Highly Sensitive Pulsed Digital Holography for Built-in Defect Analysis with a Laser Excitation

A highly sensitive method is presented for noninvasive defect analysis on thin structures with a Q-switched double-pulsed ruby laser with frequency doubling (347 nm). In our research we feature an all-optical arrangement, where a focused laser pulse derived from the same ruby laser (694 nm) acts as a built-in synchronous excitation source for digital holographic interferometry. The recordings are made with a CCD camera for capturing two holograms (two states of the specimen) corresponding to the two UV laser pulses with a short time separation (10-50 mus). Subtraction of the phase distribution in two digital holograms gives a fringe phase map that shows the change in deformation of the specimen between the recordings. The advantage of the proposed method is two fold. First, the use of a shorter wavelength results in a higher sensitivity. Second, owing to the induced synchronous built-in optical excitation, the specimen is not subjected to any external physical excitation devices. Experimental results are presented on identification and evaluation of defects in thin metal sheets.

Crystallization and characterization of Pumilo: a novel RNA binding protein

Axis determination in early Drosophila embryos is controlled, in part, by regulation of translation of mRNAs transcribed in maternal cells during oogenesis. The Pumilio protein is essential in posterior determination, binding to hunchback mRNA in complex with Nanos to suppress hunchback translation. In order to understand the structural basis of RNA binding, Nanos recruitment, and translational control, we have crystallized a domain of the Drosophila Pumilio protein that binds RNA. The crystals belong to the space group P6(3) with unit cell dimensions of a = b = 94.5 A, c = 228.9 A, alpha = beta = 90 degrees, gamma = 120 degrees and diffract to 2.6 A with synchrotron radiation. We show that the purified protein actively binds RNA and is likely to have a novel RNA binding fold due to a very high content of alpha-helical secondary structure.

Adolescent behaviour regarding reproductive health

A cross-sectional household survey was undertaken in rural areas of district Sirmaur, Himachal Pradesh, to assess the knowledge, beliefs and practices of adolescents about reproductive health. Six hundred and forty three unmarried adolescents aged 15-19 years were selected by 30-cluster sampling method from 2400 households. They were interviewed using a semi-structured schedule. Fifty-six per cent were girls. More girls (14%) were illiterate than boys (6%). Most of the boys (88%) and 58% girls knew that a female conceives through sexual intercourse. Seventy seven per cent girls and eighty seven per cent boys were aware of at least one contraceptive method. Majority of the girls (71%) and boys (82.5%) favoured termination of an unwanted pregnancy. About one-fourth respondents considered husband responsible for infertility and for sex of the baby. Boys considered night emission, poor body built and less growth of hair as reproductive health problems, whereas, girls were worried about menstruation and inadequate breast development. Almost 6% boys reported use of a contraceptive method indicating existence of pre-marital sexual activity. Knowledge on reproductive health is low and there is a big gap between actual and desired practices.

Allosteric effects of Pit-1 DNA sites on long-term repression in cell type specification

Reciprocal gene activation and restriction during cell type differentiation from a common lineage is a hallmark of mammalian organogenesis. A key question, then, is whether a critical transcriptional activator of cell type-specific gene targets can also restrict expression of the same genes in other cell types. Here, we show that whereas the pituitary-specific POU domain factor Pit-1 activates growth hormone gene expression in one cell type, the somatotrope, it restricts its expression from a second cell type, the lactotrope. This distinction depends on a two-base pair spacing in accommodation of the bipartite POU domains on a conserved growth hormone promoter site. The allosteric effect on Pit-1, in combination with other DNA binding factors, results in the recruitment of a corepressor complex, including nuclear receptor corepressor N-CoR, which, unexpectedly, is required for active long-term repression of the growth hormone gene in lactotropes.

Effect of continuing training on knowledge and practices of traditional birth attendants about maternal and newborn care

Seventy nine traditional birth attendants (TBAs) of Raipur Rani community development block, Haryana were interviewed to assess the effectiveness of continuing training in changing their knowledge and practices regarding maternal and newborn care. Seventy three percent of them reported participation in continuing training sessions. However, analysis of attendance register showed that only 35.4% had attended more than 50% sessions in year 1993. Most (83.5%) of the TBAs gave advice to pregnant women for increased food intake, 47% advised tetanus toxoid, 16.5% for more rest, and 31.6% for iron tablets. Many of them were aware of maternal complications i.e. anaemia (64.6%), oedema (26.6%), bleeding per veginum (39.2%), abnormal presentation (77.2%) and high fever (48.1%). Risks to newborn like low birth weight, fever, cough/rapid breathing and hypothermia were known to 20.2%, 31.6%, 17.7% and 1.3% of the TBAs respectively. Knowledge regarding causes of low birth weight baby like 'weak' mother, less diet in pregnancy, short birth interval and preterm delivery were reported by 69.6%, 63.3%, 12.6% and 3.8% respectively. About two fifth of TBAs advised referral to hospital in case of prolonged labour and 88.6% for very low birth weight babies. Disposable Dai Kit and weighing machine were available with 32% and 73% TBAs. Significantly higher proportion of TBAs participating in continuing training advised tetanus toxoid vaccination, appropriate feeding practices of the newborn, hospital referral in case of prolonged labour and were less inclined to advise injection to speed up labour. Therefore, efforts should be made to increase the attendance of TBAs in continuing training sessions so as to sustain modern maternal and newborn care practices acquired after initial training.

Gene repression by coactivator repulsion

We show that the IRF-2 oncoprotein represses virus-induced IFN-beta gene transcription via a novel mechanism. Virus infection induces recruitment of IRF-2 to some of the endogenous IFN-beta enhancers as part of the enhanceosome. Enhanceosomes bearing IRF-2 cannot activate transcription, due to the presence of a domain in IRF-2 that prevents enhanceosome-dependent recruitment of the CBP-Pol II holoenzyme complex. As a consequence, IRF-2 incorporation into enhanceosomes restricts the number of IFN-beta promoters directing transcription. Remarkably, deletion of the IRF-2 gene increases IFN-beta expression by expanding the number of cells capable of inducing IFN-beta gene transcription in response to virus infection.

Otomycosis: a clinicomycologic study

Otomycosis is a common fungal infection of the ear that is seen in the tropical and subtropical regions of the world. We performed mycologic analyses on debris and scraping samples from the external ear canals of 95 patients who had been clinically diagnosed with otomycosis. Seventy-one samples (74.7%) were positive for fungal growth; two of these samples contained two fungi, bringing the total number of isolates to 73. The most common pathogens were Aspergillus fumigatus (41.1% of all isolates), A niger (36.9%), and Candida albicans (8.2%).

Monomeric midkine induces tumor cell proliferation in the absence of cell-surface proteoglycan binding

Midkine (MK), a retinoic acid-inducible heparin-binding protein, is a mitogen which initiates a cascade of intracellular protein tyrosine phosphorylation mediated by the JAK/STAT pathway after binding to its high affinity p200(+)/MKR cell surface receptor in the G401 cell line [Ratovitski, E. A. (1998) J. Biol. Chem. 273, 3654-3660]. In this study, we determined the biophysical characteristics of purified recombinant murine MK and analyzed the requirements for ligand multimerization and cell surface proteoglycan binding for the G401 cell mitogenic activity of MK. Our studies indicate that the secreted form of MK (M = 13 kDa) exists in solution as an asymmetric monomer with a frictional coefficient of 1. 48 and a Stokes radius of 23.7 A. By constructing bead models of MK using the program AtoB and the program HYDRO to predict the hydrodynamic properties of each model, our data suggest that MK has a dumb-bell shape in solution composed of independent N- and C-terminal domains separated by an extended linker. This asymmetric MK monomer is a biologically active ligand with mitogenic activity on G401 cells in vitro. Neither heparin-induced formation of noncovalent MK multimers nor tissue transglutaminase II covalent multimerization of MK enhanced MK mitogenic activity in this system. Since neither heparin competition nor cell treatment with chondroitinase ABC or heparinase III abolished the mitogenic effects of MK on G401 cells, cell-surface proteoglycan binding by MK does not appear to be a requirement for its observed mitogenic effects. These results provide strong evidence that the MK-specific p200(+)/MKR has distinctive biochemical properties which distinguish it from the receptor tyrosine phosphatase cell-surface proteoglycan PTPzeta/RPTPbeta and support the hypothesis that the diverse biological effects of MK are mediated by multiple cell-specific signal transduction receptors.

Crystallization of restriction endonuclease BamHI with nonspecific DNA

Restriction endonucleases show extraordinary specificity in distinguishing specific from nonspecific DNA sequences. A single basepair change within the recognition sequence results in over a million-fold loss in activity. To understand the basis of this sequence discrimination, it is just as important to study the nonspecific complex as the specific complex. We describe here the crystallization of restriction endonuclease BamHI with several nonspecific oligonucleotides. The 11-mer, 5'-ATGAATCCATA-3', yielded cocrystals with BamHI, in the presence of low salt, that diffracted to 1.9 A with synchrotron radiation. The cocrystals belong to the space group P2(1)2(1)2(1) with unit cell dimensions of a = 114.8 A, b = 91.1 A, c = 66.4 A, alpha = 90 degrees, beta = 90 degrees, gamma = 90 degrees. This success in the cocrystallization of BamHI with a nonspecific DNA provides insights for future attempts at crystallization of other nonspecific DNA-protein complexes.

Structure of BamHI bound to nonspecific DNA: a model for DNA sliding

The central problem faced by DNA binding proteins is how to select the correct DNA sequence from the sea of nonspecific sequences in a cell. The problem is particularly acute for bacterial restriction enzymes because cleavage at an incorrect DNA site could be lethal. To understand the basis of this selectivity, we report here the crystal structure of endonuclease BamHI bound to noncognate DNA. We show that, despite only a single base pair change in the recognition sequence, the enzyme adopts an open configuration that is on the pathway between free and specifically bound forms of the enzyme. Surprisingly, the DNA drops out of the binding cleft with a total loss of base-specific and backbone contacts. Taken together, the structure provides a remarkable snapshot of an enzyme poised for linear diffusion (rather than cleavage) along the DNA.

Understanding the immutability of restriction enzymes: crystal structure of BglII and its DNA substrate at 1.5 A resolution

Restriction endonucleases are remarkably resilient to alterations in their DNA binding specificity. To understand the basis of this immutability, we have determined the crystal structure of endonuclease BglII bound to its recognition sequence (AGATCT), at 1. 5 A resolution. We compare the structure of BglII to endonuclease BamHI, which recognizes a closely related DNA site (GGATCC). We show that both enzymes share a similar alpha/beta core, but in BglII, the core is augmented by a beta-sandwich domain that encircles the DNA to provide extra specificity. Remarkably, the DNA is contorted differently in the two structures, leading to different protein-DNA contacts for even the common base pairs. Furthermore, the BglII active site contains a glutamine in place of the glutamate at the general base position in BamHI, and only a single metal is found coordinated to the putative nucleophilic water and the phosphate oxygens. This surprising diversity in structures shows that different strategies can be successful in achieving site-specific recognition and catalysis in restriction endonucleases.

Community based study of reproductive tract infections among ever married women of reproductive age in a rural area of Haryana, India

A community based study was carried out to estimate the load of reproductive tract infections (RTIs) among ever married rural women aged 15-44 years and utilisation of a mobile village based treatment facility by them, during 1997. Complete household survey was done in 10 randomly selected villages of Mahindergarh district in Haryana, India. A total of 2325 women were interviewed by auxiliary nurse midwives and were invited for medical examination in a health camp set-up in their village. Sixty-one percent (1415/2325) women reported symptoms of RTIs. Only 35% (812/2325) had their per-speculum examination done. Out of those examined, 32% (263/812) had vaginitis, 21% (175/812) had cervicits, and 19% (156/812) had pelvic inflammatory disease. Vaginal smear of those having discharge revealed that 48% (231/476) had bacterial vaginosis, 0.8% (4/476) had fungal infection 9% (44/496) had trichomonal infection and none was found to be having gonococcal infection. Tests for chlamydial infection could not be performed as the cost was not affordable. Eighty-nine percent of women who reported symptoms of RTIs had not consulted anyone for their problem prior to our village based camp. Only 42% symptomatic and 24% asymptomatics availed the services even in the village based camps. Study revealed high load of reproductive tract infections and low utilisation of treatment facility. In-depth studies are required to understand for high RTI morbidity load and low treatment seeking rate so as to design an appropriate RTI control programme.

Structure and ligand of a histone acetyltransferase bromodomain

Histone acetylation is important in chromatin remodelling and gene activation. Nearly all known histone-acetyltransferase (HAT)-associated transcriptional co-activators contain bromodomains, which are approximately 110-amino-acid modules found in many chromatin-associated proteins. Despite the wide occurrence of these bromodomains, their three-dimensional structure and binding partners remain unknown. Here we report the solution structure of the bromodomain of the HAT co-activator P/CAF (p300/CBP-associated factor). The structure reveals an unusual left-handed up-and-down four-helix bundle. In addition, we show by a combination of structural and site-directed mutagenesis studies that bromodomains can interact specifically with acetylated lysine, making them the first known protein modules to do so. The nature of the recognition of acetyl-lysine by the P/CAF bromodomain is similar to that of acetyl-CoA by histone acetyltransferase. Thus, the bromodomain is functionally linked to the HAT activity of co-activators in the regulation of gene transcription.

Reciprocal interactions of Pit1 and GATA2 mediate signaling gradient-induced determination of pituitary cell types

The mechanisms by which transient gradients of signaling molecules lead to emergence of specific cell types remain a central question in mammalian organogenesis. Here, we demonstrate that the appearance of four ventral pituitary cell types is mediated via the reciprocal interactions of two transcription factors, Pit1 and GATA2, which are epistatic to the remainder of the cell type-specific transcription programs and serve as the molecular memory of the transient signaling events. Unexpectedly, this program includes a DNA binding-independent function of Pit1, suppressing the ventral GATA2-dependent gonadotrope program by inhibiting GATA2 binding to gonadotrope- but not thyrotrope-specific genes, indicating that both DNA binding-dependent and -independent actions of abundant determining factors contribute to generate distinct cell phenotypes.