Influence of Radiation Fractionation on Immune Repertoire Diversity in Solid Tumor Patients

PURPOSE/OBJECTIVE(S)

Radiation (RT)-induced lymphopenia (RIL) occurs in up to 75% of patients undergoing RT and is associated with worse tumor control and survival across a spectrum of solid tumors. Patients undergoing hypofractionated RT are at lower risk of RIL compared with patients treated with more prolonged RT courses. However, it is unknown whether immune repertoire diversity is similarly affected by fractionation scheme in patients undergoing RT. This prospective study analyzed RT-induced changes in immune repertoire diversity in patients treated with conventionally (CFRT) vs hypofractionated RT (HFRT).

MATERIALS/METHODS

RNA-based T and B cell receptor sequencing was performed on peripheral lymphocytes collected prospectively before RT and within 4 weeks of the last RT fraction from 23 patients (18 men, 5 women, median age 67 y) with primary solid tumors undergoing CFRT (≤3 Gy/day x ≥10 days, n = 13) or HFRT (≥5 Gy/day x ≤5 days, n = 10). Absolute lymphocyte counts (ALC; cells/μL) were obtained from clinical laboratory data. The number of unique CDR3 receptors (uCDR3) and Shannon entropy were used to monitor changes in T (TCR Vβ) and B (BCR IgH) receptor diversity.

RESULTS

ALC decreased after RT in 90% (20/22) of patients (mean pre-RT ALC 1830 vs 1040 post-RT, p <0.001). Mean % ALC loss was greater in CFRT vs HFRT patients (44.3 vs. 35.2%). After RT, entropy in IgH and Vβ decreased in 18/23 (78%) and 17/23 (74%) patients, respectively; uCDR3 in IgH and Vβ decreased in 14/23 (61%) and 15/23 (65%). Among patients with concordant decreases in ALC and uCDR3, a moderate correlation between magnitude of ALC loss and uCDR3 levels in the T-cell receptor Vβ was observed (r = 0.64, p = 0.02). For both receptor species studied (IgH and Vβ), HFRT patients were more likely to have an increase in either entropy or uCDR3 in the face of decreased ALC (36 vs 15%, X2 p = 0.03). Furthermore, while decreases in entropy were observed among the CFRT patients for both IgH (median entropy 10.4 vs 9.4, p = 0.06) and Vβ (9.7 vs 8.1, p = 0.02), entropy did not significantly change following RT in the HFRT patients (IgH 10.6 vs 10.4, p = 0.74 and Vβ 10.9 vs 10.8, p = 0.24).

CONCLUSION

RT-induced changes in immune repertoire diversity are variably reflected in the peripheral ALC. Both HFRT and CFRT depleted circulating lymphocytes, but patients undergoing HFRT were more likely to experience increases in T and B cell diversity metrics despite lymphopenia. It is therefore possible that relative sparing of repertoire diversity among patients undergoing HFRT could increase the likelihood of tumor antigen recognition by peripheral blood lymphocytes. As immune repertoire diversity is associated with the likelihood of response to immunotherapy, these findings also have implications for RT-immunotherapy combinations. Further study is required to understand the relationship between RT exposure to circulating lymphocyte populations and immune repertoire diversity.

Combination Immunotherapy with Partial Versus Whole Tumor Radiotherapy in a Preclinical Melanoma Tumor Model

PURPOSE/OBJECTIVE(S)

Partial tumor radiotherapy (PTRT) with immune checkpoint inhibition (ICI) is currently the subject of clinical trials and may be used clinically for large volume tumors when the full gross tumor volume (GTV) cannot be safely treated with full dose. PTRT delivers RT to a portion of the GTV, underdosing or not treating the remainder of the GTV, hypothesizing that ICI-mediated tumor infiltrating lymphocyte (TIL) infiltration will produce adequate disease control in un- or under-irradiated GTV. Standard treatment is whole tumor radiotherapy (WTRT), and potential differences in disease control between PTRT and WTRT with ICI have not been robustly assessed. We hypothesized that PTRT with ICI and WTRT with ICI will demonstrate similar tumor regression, and both RT regimens will demonstrate superior tumor regression as compared to ICI alone.

MATERIALS/METHODS

B78 melanoma flank tumors were generated in C57B/L6 mice, with randomization at tumor size of 1 cm to experimental cohorts of PTRT + ICI and WTRT + ICI and control groups of no RT ± ICI. Custom lead shields were fabricated to deliver 16 Gy single fraction PTRT (50% tumor treatment) and WTRT, with dosimetry confirmation via radiochromic film. ICI was delivered through I.P. injection of murine anti-CTLA4 and anti-PD-L1 at days 0, 3, and 6 post-RT. Tumor regression was assessed via differences in tumor volume at ten days post completion of ICI, and mean cohort tumor volumes were compared with ANOVA (α <0.05). Variances between individual cohorts were assessed via t-test (α <0.05).

RESULTS

Treatment cohorts demonstrated significant variance in tumor volume at ten days following treatment completion (p = 0.007, Table 1). WTRT + ICI demonstrated superior tumor regression when compared to PTRT + ICI (p = 0.006), ICI alone (p = 0.002), and control cohorts (p = 0.013). There was no difference in tumor regression between PTRT + ICI and ICI alone (p = 0.709), and PTRT + ICI did not achieve significant regression when compared to control (p = 0.083). Tumor regression did not differ between cohorts receiving no RT ± ICI (p = 0.103).

CONCLUSION

Our results in this ICI resistant melanoma model demonstrated superior tumor regression with WTRT + ICI as compared to PTRT + ICI and ICI alone, suggesting that even with concurrent ICI, PTRT may not be sufficient treatment for melanoma. PTRT + ICI tumor regression was similar to ICI alone, suggesting that PTRT may not overcome immune resistance in the unirradiated tumor volume. Further investigation of optimal RT regimens to potentiate ICI response is warranted and correlative studies examining spatial immunomodulation in unirradiated and irradiated portions of the same tumor are underway.

Good Practices for the Laboratory Performance Testing of Aqueous Oral Inhaled Products (OIPs): an Assessment from the International Pharmaceutical Aerosol Consortium on Regulation and Science (IPAC-RS)

Multiple sources must be consulted to determine the most appropriate procedures for the laboratory-based performance evaluation of aqueous oral inhaled products (OIPs) for the primary measures, dose uniformity/delivery, and aerodynamic particle (droplet) size distribution (APSD). These sources have been developed at different times, mainly in Europe and North America, during the past 25 years by diverse organizations, including pharmacopeial chapter/monograph development committees, regulatory agencies, and national and international standards bodies. As a result, there is a lack of consistency across all the recommendations, with the potential to cause confusion to those developing performance test methods. We have reviewed key methodological aspects of source guidance documents identified by a survey of the pertinent literature and evaluated the underlying evidence supporting their recommendations for the evaluation of these performance measures. We have also subsequently developed a consistent series of solutions to guide those faced with the various associated challenges when developing OIP performance testing methods for oral aqueous inhaled products.

Reducing g(2)(0) of a parametric down-conversion source via photon-number resolution with superconducting nanowire detectors

Multiphoton contributions pose a significant challenge for the realisation of heralded single-photon sources (HSPS) based on nonlinear processes. In this work, we improve the quality of single photons generated in this way by harnessing the photon-number resolving (PNR) capabilities of commercial superconducting nanowire single-photon detectors (SNSPDs). We report a 13 ± 0.4% reduction of g⁽²⁾(τ = 0), even with a collection efficiency in the photon source of only 29.6%. Our work demonstrates the first application of the PNR capabilities of SNSPDs and shows improvement in the quality of an HSPS with widely available technology.

Measuring the Joint Spectral Mode of Photon Pairs Using Intensity Interferometry

The ability to manipulate and measure the time-frequency structure of quantum light is useful for information processing and metrology. Measuring this structure is also important when developing quantum light sources with high modal purity that can interfere with other independent sources. Here, we present and experimentally demonstrate a scheme based on intensity interferometry to measure the joint spectral mode of photon pairs produced by spontaneous parametric down-conversion. We observe correlations in the spectral phase of the photons due to chirp in the pump. We show that our scheme can be combined with stimulated emission tomography to quickly measure their mode using bright classical light. Our scheme does not require phase stability, nonlinearities, or spectral shaping and thus is an experimentally simple way of measuring the modal structure of quantum light.

Single-shot discrimination of coherent states beyond the standard quantum limit

The discrimination of coherent states is a key task in optical communication and quantum key distribution protocols. In this work, we use a photon-number-resolving detector, the transition-edge sensor, to discriminate binary-phase-shifted coherent states at a telecom wavelength. Owing to its dynamic range and high efficiency, we achieve a bit error probability that unconditionally exceeds the standard quantum limit (SQL) by up to 7.7 dB. The improvement to the SQL persists for signals containing up to approximately seven photons on average and is achieved in a single shot (i.e., without measurement feedback), thus making our approach compatible with larger bandwidths.

Delivering the Promise of Sendai Framework for Disaster Risk Reduction in Fragile and Conflict-Affected Contexts (FCAC): A Case Study of the NGO GOAL's Response to the Syria Conflict

The Sendai Framework for Disaster Risk Reduction (SFDRR) has helped to reduce global disaster risk, but there has been a lack of progress in disaster risk reduction (DRR) for people living in fragile and conflict affected contexts (FCAC). Given the mounting evidence that DRR cannot be implemented through conventional approaches in FCAC, serious efforts must be made to understand how to meet SFDRR's goals. This paper offers a case study of international non-governmental organization GOAL's programming that responds to the protracted crisis in Syria, with critical discussion on SFDRR and how to adapt humanitarian relief and disaster resilience.

Practitioner Approaches to Measuring Community Resilience: The Analysis of the Resilience of Communities to Disasters Toolkit

To be useful for operational programs, measures of resilience must not just be valid, but be easy to use and useful. Unfortunately, while resilience measurement techniques have progressed tremendously over the past decade, most progress has been on improving validity rather than utility and ease of use. In this article we present a new tool for measuring community resilience that incorporates issues of utility and ease of use, the Analysis of Resilience of Communities to Disasters (ARC-D) toolkit. The toolkit was developed over the course of ten years by the international humanitarian and development organization GOAL to enable aid organizations to measure community resilience in a way that supports resilience building interventions. It offers an approach to measurement that is cognizant of the resilience policy landscape, including the Sendai Framework, approaches to data collection and measurement uses relevant to aid agencies. We first present the core tenants of community resilience measurement before describing the toolkit, which consists of 30 measures, a guidebook, and an online platform. To illustrate its use, we a case study of a resilience building program in Tegucigalpa, Honduras. By developing one of the first resilience toolkits focused beyond validity and providing a description of how such an assessment works, this article has implications for resilience researchers and practitioners.

'To minimise that risk, there are some costs we incur': Examining the impact of gender-based violence on the urban poor

Urban environments marked by violence create fear that can have real impacts on the urban poor, particularly women and girls. Any efforts to tackle poverty and promote health must address the impacts to their access to livelihoods and education, healthcare, markets, and social support that underlie wellbeing. This study aimed to elucidate specific impacts that violence and fear have on the very poor in rapidly growing cities and the coping strategies employed. This multi-country qualitative study was conducted in Dhaka, Bangladesh, Port-au-Prince, Haiti; and Addis Ababa, Ethiopia. Participants in all three cities employed similar tactics to avoid violence. People adjusted how, when, and where they travel and how they interact with people who threaten them. These coping strategies led participants to spend more money on goods and to restrict access to livelihood opportunities, education, healthcare, and social activities. Women are impacted more than men in all spheres and city specific differences are highlighted. Residents of urban slums, particularly women, in these three cities cope with urban violence in many ways, suffering consequences in a range of categories - leading to significant impacts to their own health and well-being and their families.

Quantum-enhanced interferometry with large heralded photon-number states

Quantum phenomena such as entanglement can improve fundamental limits on the sensitivity of a measurement probe. In optical interferometry, a probe consisting of N entangled photons provides up to aN enhancement in phase sensitivity compared to a classical probe of the same energy. Here, we employ high-gain parametric down-conversion sources and photon-number-resolving detectors to perform interferometry with heralded quantum probes of sizes up to N = 8 (i.e. measuring up to 16-photon coincidences). Our probes are created by injecting heralded photon-number states into an interferometer, and in principle provide quantum-enhanced phase sensitivity even in the presence of significant optical loss. Our work paves the way towards quantum-enhanced interferometry using large entangled photonic states.

Health outcomes of crisis driven urban displacement: A conceptual framework

With urbanisation, cities are increasingly home to greater proportions of the world's population. As this transition has significant implications on human health, the epidemiology of diseases among relatively stable urban populations is growing. As humanitarian crises increasingly drive people to urban centers rather than traditional refugee camps, however, rapid and massive urban displacements will increase in frequency. This paper explores the idea that such urban displacements combine epidemiological features of forced migration, slum conditions and humanitarian disaster contexts. This paper highlights the lack of primary data and the consequent paucity of solid epidemiological literature in the aftermath of rapid massive urban displacements. A framework of health outcomes in urban displacement drawing from the above 3 phenomenon is presented and avenues for improved epidemiologic work described.

Functional Radionuclide Imaging, In-Vitro Radioiodine Uptake Estimation and RT-PCR in the Evaluation of Sodium Iodide Symporter (NIS) Expression and Functionality in Breast Cancer: A Pilot Study

Breast cancer is a common malignancy in females, which is considered as a systemic disease, whose treatment involves combined modality including systemic as well as local treatment. Recent studies have shown that breast cancer also expresses Sodium Iodide Symporter (NIS) gene, like in the thyroid, which is the factor responsible for the uptake of iodide by the thyroid, enabling radioiodine therapy of thyroid disorders. This study aimed to evaluate various radionuclide imaging characteristics, in vitro radioiodine uptake (RAIU) and evaluation of NIS expression by using Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) to explore sodium iodide symporter (NIS) expression and iodine uptake in breast cancer and to explor e whether radioiodine can be used for the diagnosis and treatment of breast cancer. Ways of differential regulation of NIS expression in breast cancer has also been explored. Female patients with palpable breast lump and histologically proven infiltrating duct carcinoma were taken up for the study, which included 50 females of mean age 49 years. (range: 23-73 years). The patients were categorized into different groups, depending on the type of the study performed. The uptake patterns in various imaging modalities were analyzed and compared with invitro and RT-PCR studies. 68 % of breast cancer cases showed (99m)Tc-pertechnetate uptake at the initial images. This finding could partly be due to tumor vascularity, which is usually higher compared to the normal tissues. The uptake in the delayed imaging could be related to that due to NIS in the breast. Use of perchlorate or stable iodine did not alter the pertechnetate uptake pattern in breast tumor. Good correlation between (99m)Tc-pertechnetate and (99m)Tc-tetrofosmin uptake in breast cancer was demonstrated. In vitro radioactive iodine uptake in the breast tumor was significantly higher than that in the normal breast tissue. Only 42 % of breast tumor samples studied using RT-PCR showed NIS expression. Correlation between (99m)Tc-pertechnetate uptake and NIS expression could not be well established. Further studies with higher dose of radioiodine and/or mechanisms of differentially blocking the thyroid are required to assess the feasibility of radioiodine therapy for breast cancer.

The high cost of diarrhoeal illness for urban slum households-a cost-recovery approach: a cohort study

OBJECTIVES

Rapid urbanisation has often meant that public infrastructure has not kept pace with growth leading to urban slums with poor access to water and sanitation and high rates of diarrhoea with greater household costs due to illness. This study sought to determine the monetary cost of diarrhoea to urban slum households in Kaula Bandar slum in Mumbai, India. The study also tested the hypotheses that the cost of water and sanitation infrastructure may be surpassed by the cumulative costs of diarrhoea for households in an urban slum community.

DESIGN

A cohort study using a baseline survey of a random sample followed by a systematic longitudinal household survey. The baseline survey was administered to a random sample of households. The systematic longitudinal survey was administered to every available household in the community with a case of diarrhoea for a period of 5 weeks.

PARTICIPANTS

Every household in Kaula Bandar was approached for the longitudinal survey and all available and consenting adults were included.

RESULTS

The direct cost of medical care for having at least one person in the household with diarrhoea was 205 rupees. Other direct costs brought total expenses to 291 rupees. Adding an average loss of 55 rupees per household from lost wages and monetising lost productivity from homemakers gave a total loss of 409 rupees per household. During the 5-week study period, this community lost an estimated 163 600 rupees or 3635 US dollars due to diarrhoeal illness.

CONCLUSIONS

The lack of basic water and sanitation infrastructure is expensive for urban slum households in this community. Financing approaches that transfer that cost to infrastructure development to prevent illness may be feasible. These findings along with the myriad of unmeasured benefits of preventing diarrhoeal illness add to pressing arguments for investment in basic water and sanitation infrastructure.

Human trafficking in the emergency department

Human trafficking continues to persist, affecting up to 200 million people worldwide. As clinicians in emergency departments commonly encounter victims of intimate partner violence, some of these encounters will be with trafficking victims. These encounters provide a rare opportunity for healthcare providers to intervene and help. This case report of a human trafficking patient from a teaching hospital illustrates the complexity in identifying these victims. Clinicians can better identify potential trafficking cases by increasing their awareness of this phenomenon, using qualified interpreters, isolating potential victims by providing privacy and using simple clear reassuring statements ensuring security. A multidisciplinary approach can then be mobilized to help these patients.

Non-obstructed femoral hernia containing ascending colon, caecum, appendix and small bowel with concurrent bilateral recurrent inguinal hernia

Femoral hernias, which are less common than inguinal hernias and more often found in females, occasionally contain more than just small intestine and omentum. Uncommon contents reported in femoral hernia sacs include caecum, appendix, Meckel's diverticulum (Littre hernia), testis, ovary, transverse colon and even stomach or kidney. Strangulation of femoral hernias containing appendix, small intestine and caecum, and Meckel's diverticulum are well reported in the literature. Here, we report a case of a male patient having bilateral femoral hernia with bilateral recurrent inguinal hernia. A huge, right-sided femoral hernia contained terminal ileum, appendix, caecum and ascending colon, which were irreducible but neither obstructed nor strangulated. The patient was operated on with a Pfannenstiel incision together with an infrainguinal incision. For reduction of content, an inguinal ligament was also incised. Bilateral preperitoneal, polypropylene mesh hernioplasty was performed along with rolled plug placement in the right femoral canal. The patient had an uneventful post operative recovery and no recurrence in 6 months of follow up.

Postselective two-photon interference from a continuous nonclassical stream of photons emitted by a quantum dot

We report an electrically driven semiconductor single-photon source capable of emitting photons with a coherence time of up to 400 ps under fixed bias. It is shown that increasing the injection current causes the coherence time to reduce, and this effect is well explained by the fast modulation of a fluctuating environment. Hong-Ou-Mandel-type two-photon interference using a Mach-Zehnder interferometer is demonstrated using this source to test the indistinguishability of individual photons by postselecting events where two photons collide at a beam splitter. Finally, we consider how improvements in our detection system can be used to achieve a higher interference visibility.

Airway function and markers of airway inflammation in patients with treated hypothyroidism

BACKGROUND

There is increasing evidence of an association between organ specific autoimmune diseases, particularly autoimmune thyroid disease and respiratory morbidity. A study was undertaken to determine whether patients with autoimmune thyroid disease have objective evidence of airway inflammation and dysfunction.

METHODS

Twenty six non-smoking women with treated hypothyroidism and 19 non-smoking controls completed a symptom questionnaire and underwent full lung function tests, capsaicin cough reflex sensitivity measurement, methacholine challenge test, and sputum induction over two visits.

RESULTS

Symptoms of cough (p = 0.01), dyspnoea (p = 0.01), sputum production (p = 0.004), and wheeze (p = 0.04) were reported more commonly in patients than controls. Patients with hypothyroidism had heightened cough reflex sensitivity compared with controls (geometric mean concentration of capsaicin causing five coughs: 40 v 108 mmol/l; mean difference 1.4 doubling doses; 95% confidence interval of difference 0.4 to 2.5; p = 0.008) and a significantly higher proportion of patients had airway hyperresponsiveness (methacholine provocative concentration (PC(20)) <8 mg/ml: 38% v 0%; p = 0.016). Patients with hypothyroidism also had a significantly higher induced sputum total neutrophil cell count (p = 0.01), total lymphocyte count (p = 0.02), and sputum supernatant interleukin-8 concentrations (p = 0.048).

CONCLUSION

Patients with treated hypothyroidism report more respiratory symptoms and have objective evidence of airway dysfunction and inflammation.

Escitalopram Versus Citalopram and Sertraline: A Double-Blind Controlled, Multi-centric Trial in Indian Patients with Unipolar Major Depression

The present randomized, double blind, parallel group, controlled, multi-centric trial was designed to evaluate the efficacy and tolerability of escitalopram in comparison with citalopram and sertraline in the treatment of major depressive disorder. Outpatients (N=214) with an ongoing/newly diagnosed ICD-10 major depressive episode and a Hamilton Rating Scale for Depression (HAM-D) score of > 18 were randomly assigned to citalopram, 20-40 mg/day (74 patients), escitalopram, 10-20 mg/day (69 patients) and sertraline, 50-150 mg/day (71 patients), for a 4-week double-blind treatment period, with dosage adjustment (after 2 weeks of treatment) according to the response to treatment. Clinical response was evaluated by the 17 items HAM-D and the Clinical Global Impression (CGI) scales, which were recorded at baseline and at weekly intervals. Tolerability was evaluated by observed/spontaneously reported adverse changes in laboratory parameters (baseline and after 4 weeks). Response rate was defined as a decrease in HAM-D score by 50% from baseline and remission rate was defined as a HAM-D score of < 8. Response rate at the end of two week were 58% for escitalopram (10mg/day), 49% for citalopram (20mg/day) and 52% for sertraline (50-100mg/day). Response rate at the end of four week were 90% for escitalopram (10-20mg/day), 86% for citalopram (20-40mg/day) and 97% for sertraline (100-150mg/day). The Remission rates at the end of four weeks were 74% for escitalopram, 65% for citalopram and 77% for sertraline. Adverse experiences were reported by 45% of patients in escitalopram group, 58% patients in citalopram and 56% patients in the sertraline group. Additionally, there were lesser dropouts and lesser requirement for dose escalation in escitalopram than in citalopram and sertraline group. In conclusion Escitalopram, the Senantiomer of the citalopram is a safe and effective antidepressant in the Indian population. It has potentially superior efficacy than citalopram and a comparable efficacy to sertraline with fewer side effects than both citalopram and sertraline.

Chronic tonsillar enlargement and cough: preliminary evidence of a novel and treatable cause of chronic cough

Tonsillar enlargement is sometimes seen in patients with otherwise unexplained chronic cough although its significance is unclear. In this study, the authors set out to test the hypothesis that cough symptoms and cough reflex sensitivity will improve after tonsillectomy in patients with otherwise unexplained chronic cough and enlarged tonsils. Eight consecutive patients with unexplained chronic cough and enlarged tonsils were recruited from 236 patients seen in a cough clinic between 2000 and 2001. Six patients with enlarged tonsils and no cough who were undergoing tonsillectomy for other reasons were recruited as a control group. All patients rated cough severity on a cough visual analogue score (0-100 mm) and had capsaicin cough reflex sensitivity measurement twice before and again 3 months after tonsillectomy. Patients with a chronic cough had heightened cough reflex sensitivity compared with the control group at baseline. There was a significant improvement in mean cough visual analogue score 3 months after tonsillectomy in patients with chronic cough (mean difference 30 mm; 95% confidence interval of difference 8-51 mm). The geometric mean concentration of capsaicin required to cause five coughs increased from 4 to 207 micromol L(-1) after tonsillectomy in patients with chronic cough (mean difference from baseline 5.6 doubling concentrations; 95% confidence interval of difference 3.1-8.2). There was no change in cough reflex sensitivity in control patients after tonsillectomy. These preliminary findings suggest for the first time a possible role for tonsillectomy in patients with enlarged tonsils in whom other causes of cough have been ruled out.

Spontaneous cerebrospinal fluid leakage and middle ear encephalocele in seven patients

Isolated cases of spontaneous cerebrospinal fluid (CSF) leakage with and without middle ear encephalocele have been reported. These leaks are usually accompanied by episodes of recurrent meningitis, hearing loss, or chronic headache. In this article, we report seven new cases of spontaneous CSF leakage. Six of these patients had conductive hearing loss and serous otitis media, and three had recurrent meningitis. Prior to a definitive diagnosis, six patients had received myringotomy tubes, which produced profuse clear otorrhea. Three patients had positive beta-2 transferrin assays. Computed tomography and magnetic resonance imaging confirmed a defect in the temporal bone tegmen. A combined transmastoid and middle fossa surgical approach with a three-layer closure was used to repair the tegmen defect. All patients had a lumbar drain placed prior to surgery. In addition to describing the seven new cases, we review the history of CSF leakage and discuss diagnostic methods, surgical findings, and our recommendations for management.

Animal model for liver dysfunction using lomustine in Wistar rats

AIM

To induce intrahepatic cholestasis in rats using lomustine 1(2-chloroethyl)-3-cyclohexyl-l-nitrosourea (CCNU).

METHODS

Doses of 10 mg, 20 mg and 30 mg/Kg body weight of CCNU were injected intraperitoneally in separate groups of animals.

RESULTS

With 10 mg/Kg body weight of CCNU, serum bilirubin levels increased for up to 72 hours and then slowly returned to normal. With a dose of 20 mg/Kg body weight of CCNU, serum bilirubin, AST, ALT and alkaline phosphatase levels increased for 72 hours and then returned to normal over 4-5 weeks. With a dose of 30 mg/Kg body weight peak levels of serum bilirubin were reached on day 17. Pathological studies were carried out after injection of 30 mg/Kg body weight of CCNU. After 72 hours hepatocytes were normal, with minimal nonspecific inflammation and bile duct proliferation. After 16 days, triaditis was observed with deposition of collagen. Focal fibrosis was also noticed. There was no significant abnormality of hepatocytes. After 75 days, hepatocytes showed focal ballooning. Bile duct proliferation was seen invading the parenchyma. Nodules of hepatocytes separated by irregular fibrous bands indicated cirrhosis.

CONCLUSIONS

An animal model of intrahepatic cholestasis has been developed using CCNU; this model may be used to assess the utility of hepatobiliary radiopharmaceuticals.

Leuprolide acetate in the management of cesarean scar endometriosis

BACKGROUND

Progestin or estrogen-progestin combination therapy has not proven useful in the treatment of endometriosis of the abdominal scar after cesarean delivery. We report our experience in managing this condition with a gonadotropin agonist.

CASE

A 22-year-old black woman with a history of two previous cesareans developed endometriosis of the abdominal scar. The extent of the lesion was estimated by computed tomographic (CT) scan, and a 6-month preoperative course of leuprolide acetate was administered. The patient exhibited prompt symptomatic response to the gonadotropin agonist, but the physical examination and CT scan findings were unchanged. Pathologic examination after surgical removal of the lesion confirmed the clinical diagnosis.

CONCLUSION

Leuprolide acetate administered to a patient with cesarean scar endometriosis was associated with an improvement in symptoms, but there was no change in lesion size.

Leuprolide acetate depot for the treatment of uterine leiomyomas. Changes in bone density, uterine volume and uterine vascular resistive index

This study measured the changes in uterine volume, uterine vascular resistive index and lumbar vertebral bone density before and after a six-month course of leuprolide acetate depot in women with uterine leiomyomas. All nine patients studied were black. The high baseline bone density of black women may provide a greater scope for the use of gonadotropin agonists as compared to women in the general population. A significant reduction in uterine volume was achieved in the patients with leuprolide therapy. Uterine vascular resistive indices were not altered consistently following leuprolide therapy in women with leiomyomas.

Pharmacokinetics of gentamicin in rabbits pretreated with nonsteroidal anti-inflammatory drugs: an interaction study

Interaction between nonsteroidal anti-inflammatory drugs (NSAIDs) and other drugs occurs relatively frequently because of the wide use of NSAIDs. Such interactions with drugs of narrow therapeutic index used in serious disease states may lead to toxicity. Gentamicin toxicity is based on its concentration in serum, and any alteration in pharmacokinetic parameters may lead to gentamicin accumulation in the body and subsequently to severe nephrotoxicity and ototoxicity. To test this hypothesis, the effect of pretreatment with NSAIDs on gentamicin pharmacokinetics was examined in rabbit. Gentamicin sulfate (5 mg/kg) was administered to rabbits pretreated with aspirin (300 mg/kg), ketorolac tromethamine (3 mg/kg), ibuprofen (20 mg/kg), and piroxicam (2 mg/kg) twice a day for 1 week. The pretreatment with NSAIDs had significant effects on the body clearance and maximum concentration. Aspirin, piroxicam and ketorolac tromethamine pretreatment had significant effects on the area under the curve of gentamicin versus time. Aspirin and ketorolac tromethamine pretreatment had significant effects on the half-life of gentamicin. Aspirin had a significant effect on the volume of distribution of gentamicin. These results suggest that pretreatment with NSAIDs alters the pharmacokinetics of gentamicin and leads to accumulation inside the body, which could result in toxicity.

Significance of MRI changes after surgery of the skull base

Magnetic resonance (MR) imaging is commonly used in the followup of patients who have undergone surgical removal of tumors from the cranial base to assess the possibility of tumor recurrence, persistence, or surgical complications. Interpretations of this study must be cautious because postoperative enhanced signals are encountered frequently. Although technological improvements continue to enhance the usefulness of MR images for followup, problems remain in differentiating between fibrotic, reconstructive changes, and tumor recurrence. In this study, the hospital records and MR findings of 215 patients who had undergone skull base surgery were reviewed. The study was prompted by negative operative exploration in three patients in whom postoperative MR images strongly suggested tumor recurrence. One-year follow-up images were available in 174 patients. Of these, 94% showed signal enhancement on the 1-year follow-up study. Progressive changes were observed in 14% of patients. The correlation of preoperative MR findings and surgery, with regard to dural involvement, vascular involvement, cranial nerve infiltration, and extent of intracranial infiltration, was analyzed in 28 patients. Methods to facilitate the detection of tumor recurrence using MR images are reviewed.

Acute urinary retention due to a free-standing broad ligament leiomyoma

A 38-year-old woman who had used oral contraceptives continuously since age 22 presented with acute urinary retention. Physical examination revealed a bladder outlet obstruction due to a large paravaginal/broad ligament mass. Magnetic resonance imaging (MRI) demonstrated that the mass was separate from the uterus which was confirmed at surgery when an isolated free-standing leiomyoma was removed.

Detection and determination of free and plasma protein-bound astemizole by thin-layer chromatography: a useful technique for bioavailability studies

A thin-layer chromatographic (TLC) procedure has been developed for the determination of astemizole in plasma as the free and as protein-bound substance. The detection and quantification were performed without using internal standards. In earlier described methods for the estimation of astemizole by high-performance liquid chromatography and radioimmunoassay, only free levels in plasma were quantified, at 3.3% of the total astemizole, with the remaining 96.7% bound to plasma protein and tissue. Our method employs proteolysis of plasma proteins by incubating plasma for 2 h in pepsin. After proteolysis the astemizole is extracted, and a known amount of the extract is spotted on precoated silica gel F 254 plates. Astemizole was quantified using a Shimadzu CS-930 dual-wavelength TLC scanner. The method provides a direct estimate of total astemizole present in the plasma.

Liquid chromatographic determination of clobetasone-17-butyrate in ointments

A liquid chromatographic (LC) method has been developed for determination of clobetasone-17-butyrate in ointment using clobetasone propionate as an internal standard. Separation was carried out on a C18 reverse-phase column using water-methanol as a mobile phase. Methylparaben and propylparaben (both sodium salt) used as preservatives did not interfere with separation. Compounds are detected photometrically at 235 nm. Mean assay results for 0.05% commercial ointments were 100.36% (n = 5). Mean recovery of clobetasone-17-butyrate added to commercial ointment was 99.89%.

Visualization of suppressed thyroid tissue by technetium-99m-tertiary butyl isonitrile: an alternative to post-TSH stimulation scanning

The autonomously functioning thyroid nodule (AFTN) is a discrete, nodular structure which operates independently of pituitary control and without relation to the remaining thyroid tissue. Presently, for the visualization of a suppressed thyroid lobe, a patient has to undergo the thyrotropin (TSH) stimulation test, which has several disadvantages. In this study we have used tertiary butyl isonitrile (99mTc-TBI), well known as a myocardial imaging agent, for visualization of the suppressed lobe. Thirteen of fourteen patients studied demonstrated a contralateral lobe on a 99mTc-TBI scan which was not visualized with a 99mTc0(4) or 131I scan. Although it is not possible to demonstrate the autonomous nature of the hyperfunctioning thyroid nodule using 99mTc-TBI, we conclude that it is feasible to use this agent to visualize the lobe without the TSH test.

Synthesis and pharmacological study of antihyperlipaemic activity of 2-substituted thieno(2,3-d)pyrimidin-4(3H)-ones

A series of 2-substituted thieno(2,3-d)pyrimidin-4-(3H) ones (1-15) was prepared by the reaction of thiophene ortho-aminoester (IV) with a variety of nitriles (V) under acidic conditions, and screened for antihyperlipaemic activity in various animal models. While most of these compounds were found active, 2-chloromethyl-5,6,7,8-tetrahydrobenzo(b)thieno(2,3-d) pyrimidin-4(3H)-one (5) was found to be the most active of all. The serum triglyceride lowering activity exhibited by 5 was found comparable to that of clofibrate and riboflavin tetrabutyrate. Compound 5 was also found to be safe as indicated by acute and chronic toxicity studies in mice and rats.

Leuprolide acetate in the management of ureteral obstruction caused by endometriosis

Endometriotic ureteral obstruction is a serious event commonly diagnosed late and therefore associated with a major risk of hydronephrotic renal atrophy. The standard therapy is surgical. However, medical treatment has been reported using danazol, progestins, and estrogen-progestin combinations, although solid documentation of the effect of hormonal therapy against ureteral endometriosis is lacking. Gonadotropin-releasing hormone (GnRH) agonist treatment of endometriosis has yielded good results but has not been adequately reported in patients with ureteric involvement. We report three patients treated with a GnRH agonist, leuprolide acetate, for 6-9 months as a preoperative course. One patient had bilateral and two had unilateral obstruction. The preoperative course relieved the obstruction in the patient with bilateral disease and in one with unilateral changes. The failure occurred in a patient with intrinsic ureteric endometriosis. This early experience suggests a place for GnRH agonist therapy for patients with ureteric obstruction due to endometriosis, probably, but not necessarily, in conjunction with a planned surgical procedure. If medical therapy is attempted, close surveillance of renal function is mandatory.

Preparation and evaluation of 99mTc-t-butylisonitrile (99mTc-TBI) for myocardial imaging: a kit for hospital radiopharmacy

A previous method was modified to obtain [99mTc(TBI)6]+ by reacting Zn(TBI)2Br2 directly with 99mTcO4- in the presence of Sn2+ ions. [Cu(TBI)4]Cl was next used as a source of TBI. On reaction with 99mTcO4- and Sn2+ ions for 3 min at 100 degrees C, [99mTc(TBI)6]+ product of radiochemical purity greater than 90% and yield greater than 70% was obtained. Data of biodistribution in rats (2-2.5% in heart) and biokinetics in rabbits were satisfactory. The kit formulation was found to be stable and also safe for administration.

Care of low birth weight babies in slums

We studied 289 newborn infants from birth till one year of age. Low birth weight babies (less than 2.5 kg) were 52.9%. Boys suffered 9.7 episodes of sickness, and girls 8.6 episodes of sickness. The mean episodes of various sicknesses, and their impact on weight gain, feeding pattern and growth pattern are discussed. Six deaths were observed, of which 4 were among the low birth weight babies. Mortality in babies born less than 2 kg was 44.4% and above 2 kg was less than 1%.

Effect of chlorine gas leak on the pulmonary functions of school children

Pulmonary function tests (PFT) were performed on 84 children studying in a Municipal School, near a plant manufacturing chemicals in Chembur, a suburb of Bombay, from where large amounts of chlorine gas leaked out on 30th August, 1985. It was found that only 23.8% had normal PFT's. 66.7% showed an obstructive pattern and 9.5% showed a restrictive pattern of PFT's. This is a preliminary report to establish the prevalence of lower PFT values in children staying in an area of air pollution in Bombay.

Klebsiella pneumoniae osteomyelitis in sickle cell anemia

A case of Klebsiella pneumoniae osteomyelitis in a patient with sickle cell anemia is reported. The literature is briefly reviewed. The case is presented because of the rarity of Klebsiella pneumonia osteomyelitis in sickle cell disease.

Clinical evaluation of 99mTc(V)-dimercapto succinic acid (DMSA) for imaging medullary carcinoma of thyroid and its metastasis

99mTc(V)-DMSA kits developed by the Radiopharmaceutical Division, Bhabha Atomic Research Centre, have been evaluated for potential use in scanning medullary carcinoma of the thyroid and its metastases. There were 15 patients with proved medullary carcinoma and 6 patients with other differentiated thyroid carcinoma. Amongst the 15 patients with medullary carcinoma, 12 (80%) showed positive localisation either in the primary or one or more metastatic sites. None of the six patients with carcinoma other than medullary showed increased concentration of 99mTc(V)-DMSA. Of the 37 known metastatic sites in 15 patients with medullary carcinoma, 24 showed concentration of 99mTc(V)-DMSA (64.9%). In addition, 99mTc(V)-DMSA concentration was seen in 14 sites where no evidence of metastasis was revealed. The incidence of 99mTc(V)-DMSA concentration in soft tissue and bone metastasis was similar.

Calcium antagonists and blood glucose in normal rabbits

The effects of the calcium antagonists verapamil and nifedipine on blood glucose levels, glucose tolerance, insulin secretion during glucose tolerance and hypoglycaemic effect of tolbutamide were studied in normal nondiabetic rabbits. Daily dosage of 40 mg/kg verapamil and 5 mg/kg nifedipine given orally up to 7 days did not affect blood glucose level, glucose tolerance, insulin secretion during glucose tolerance and hypoglycaemic activity of tolbutamide 250 mg/kg p.o.

Influence of tablet dissolution on furosemide bioavailability: a bioequivalence study

In order to evaluate the in vitro dissolution and in vivo bioavailability relationship for furosemide, a bioequivalence study was carried out. Furosemide (40 mg) was administered orally to 12 normal volunteers in a 6 x 6 crossover design using six products (five tablets and one solution) obtained from three pharmaceutical companies. Plasma and urine concentrations of furosemide were quantitated by high-performance liquid chromatography (HPLC). Plasma furosemide profiles were analyzed by non-compartmental methods. Compared to the oral solution, all of the formulations exhibited lower peak furosemide concentrations, longer mean residence times, and, in some cases, diminished bioavailability (range, 66-96%). Similar results were obtained when the reference product (a rapidly dissolving tablet) was used as the standard. All of the products failed the 75/75 rule when compared to either reference standard, apparently because of large intersubject variability. The total amount of furosemide excreted in urine could be associated with the percentage drug dissolved (in vitro) at 30 min. The pH 5.6 dissolution medium (compared to pH 4.6) appears to be an appropriate test medium for assuring batch uniformity and bioequivalence of furosemide products.

Preparation and evaluation of 99mTc(V)-DMSA complex: studies in medullary carcinoma of thyroid

Consequent to the promising results reported with 99mTc(V)-DMSA for imaging certain types of soft tissue tumors, we have developed methods to prepare this radiopharmaceutical in three ways: from freshly prepared reagents, through the use of a two component kit and use of the standard renal DMSA kit by a modified recipe. The 99mTc(V)-DMSA complex has been subjected to paper electrophoretic and chromatographic procedures and also biodistribution studies. The distinctly different behaviour of this new product compared to that of the well known renal DMSA complex has been clearly established. Scintiimaging in a preliminary clinical trial in patients with medullary carcinoma of the thyroid has been encouraging.