Cardiac Sparing with Volumetric Modulated Arc Therapy Enabled Total Body Irradiation (CS VMAT-TBI)

PURPOSE/OBJECTIVE(S)

Volumetric modulated arc therapy (VMAT) enabled total body irradiation (TBI) has replaced conventional TBI in our institution given the improved treatment accuracy, patient comfort, and dose modulation ability. The risk of cardiovascular disease is several folds higher among transplant patients who receive TBI, likely related to dose to the heart. We hypothesize that a cardiac-sparing (CS) VMAT-TBI technique is feasible and can meaningfully reduce dose to the heart while still adequately covering nearby lymphatic tissue.

MATERIALS/METHODS

VMAT-TBI is delivered via multi-isocentric external beams in a frame-based setup. Heart is contoured as per published guidelines. A lymph node contour, which includes tonsils, neck nodal stations, mediastinal, abdominal, retroperitoneal, and pelvic nodes is created. Coverage of the lymph node contour is prioritized over organ-sparing during inverse optimization; with a goal of V90% greater than 99.5% and mean dose less than 800 cGy for the lymph nodes and heart, respectively. An IRB-approved retrospective review was performed with mean heart dose collected for all patients treated with CS VMAT-TBI and compared to a representative cohort of five patients treated with VMAT-TBI without cardiac sparing.

RESULTS

Thirty-one patients were treated with CS VMAT-TBI between 2020-2022 with a median follow up time of 11.5 months. Mean heart dose was 796 ± 71 cGy in the CS VMAT-TBI compared to 1247 ± 29 cGy in the VMAT-TBI group without cardiac sparing (p < 0.001). Of those treated with CS VMAT-TBI, three patients relapsed; one relapse occurred in bone marrow only, one relapse occurred in bone marrow and cervical, thoracic, and intra-abdominal lymphoid tissues, and one patient was simulated but never received induction therapy due to overt progression. 100-day relapse-free survival and overall survival were 82.5% and 86.2%, respectively. Median survival time has not been met.

CONCLUSION

Cardiac sparing is feasible in VMAT-TBI and is associated with significant decrease in mean heart dose of ∼450 cGy. This is estimated to confer a 33.3% decreased absolute risk for lifetime major coronary events compared to patients treated with VMAT-TBI without cardiac sparing. Although limited by short follow-up time, there does not appear to be a significant risk for early relapse despite de-escalating cardiac tissue, likely due to prioritizing coverage of lymph nodes. Prospective clinical studies are needed to further validate cardiac and other organ at risk sparing VMAT-TBI techniques.

Role of Fractionation in Local Control of Spinal Metastases Treated with Stereotactic Radiosurgery

PURPOSE/OBJECTIVE(S)

Optimal fractionation of spinal stereotactic radiosurgery (SRS) for spine metastases remains unknown. Retrospective data suggest decreased local failure (LF) with fractionated SRS of brain metastases. We evaluated our institutional outcomes of spinal SRS with the hypothesis that fractionation improves the rate of local failure compared to single-fraction treatment.

MATERIALS/METHODS

This IRB-approved, retrospective analysis included patients with spine metastases treated with spinal SRS between October 2002 and November 2014 with evaluable follow-up imaging and no prior irradiation to the given segment. The exposure of interest was single- or multi-fraction SRS with a primary endpoint of the cumulative incidence of LF with death as a competing risk. We assessed bivariate associations between fractionation and single-fraction equivalent dose (SFED in Gy10) as well as high-risk features, defined as epidural extension (Bilsky Scale), paraspinous extension, and gastrointestinal (GI) vs non-GI primary. We calculated the rates of LF and vertebral body compression fracture (VCF) at 1-year, and assessed LF by fractionation when limited only to courses receiving SFED>18 Gy. We analyzed the association between fractionation and LF using subdistribution hazard ratios (SHR) estimated from competing risks regression with death as a competing risk and adjusting for lesion-specific characteristics as well as SFED to determine contribution of these variables to the estimated effect of fraction number on LF. We calculated relative attenuation for the contribution of SFED to this association, defined as [SHRfractions-SHRfractions+SFED] ÷ [SHRSFED-1].

RESULTS

In 293 patients with 516 spinal segments, lesions treated with single fraction compared to multi-fraction SRS had less epidural (19% vs 36%, p<0.001) and paraspinous (20% vs 35%, p<0.001) extension, more GI histology (17% vs 10%, p = 0.039), received a higher mean SFED (18.3 Gy vs. 16.6 Gy, p<0.001), and had a lower 1-year LF (8% vs 14%, p = 0.02), with no difference in VCF (7% vs. 5%, p = 0.38). After adjusting for high-risk features, single fraction SRS was associated with lower LF (SHR = 0.45, 95% CI 0.24-0.84, p = 0.02). After adjustment for SFED, this association of fractionation was attenuated by 53% and became insignificant (SHR = 0.78, 95% CI 0.44-1.37, p = 0.38). Overall, 1-year LF for SFED>18 Gy was 6% compared to 15% for <18 Gy (p<0.001). When limited to courses with SFED>18 Gy (n = 261), single fraction SRS had no improvement in 1-year LF compared to multi-fraction (6.6% vs 4.6%, p = 0.77).

CONCLUSION

Single fraction SRS was associated with better local control compared to multi-fraction; however, much of this association was attenuated by SFED but not by high-risk features of treated lesions. To clarify the role of fractionation, we have initiated a prospective, randomized trial of single vs. multi-fraction SRS utilizing the same SFED.

Response-Adapted Omission of Radiotherapy in Pediatric Patients with Intermediate- and High-Risk Hodgkin Lymphoma Treated per EuroNet-PHL-C1: A Single Institution Analysis of Outcomes and Patterns of Failure

PURPOSE/OBJECTIVE(S)

EuroNet-PHL-C1 demonstrated that 40% of intermediate- and high-risk pediatric Hodgkin lymphoma (HL) patients treated with OEPA-COPDAC chemotherapy achieved adequate response (AR) at early response assessment (ERA), and thus were able to omit radiotherapy (RT). However, patterns of failure with this treatment paradigm, and specifically, whether or not all initial sites of disease require RT for those with inadequate response (IR) at ERA is unknown. The purpose of our study is to examine outcomes and patterns of failure for those treated per EuroNet-PHL-C1 at our institution. Our hypothesis is that limiting RT to only sites of IR at ERA does not result in increased failures.

MATERIALS/METHODS

An IRB-approved retrospective review of all intermediate- and high-risk classical HL pediatric patients treated at our institution per EuroNet-PHL-C1 between 2015 and 2021 was performed. Patients were treated per protocol with radiation omitted for those with AR (Deauville 1-2 and >75% tumor shrinkage) at ERA (PET/CDT after 2 cycles of chemo). For those with IR who required RT, only sites of IR (Deauville 3-5) at ERA were treated using involved site radiation treatment (ISRT), instead of all initial sites of disease as on EuroNet-PHL-C1. Outcomes including overall survival (OS) and progression free survival (PFS) were calculated using Kaplan-Meier curves and patterns of failure were classified as either initial site only, new site only, or initial and new sites.

RESULTS

A total of 35 patients were identified, of which 33 had evaluable follow up with median follow up of 33 months. The median age at diagnosis was 14 (range, 4-18) and 48% were female. Of the 33, 7 (21%) had IR at ERA and thus required RT, while 26 (79%) were spared RT. In the group who received RT, 4/7 (57%) had initial B-symptoms and 4/7 (57%) had initial bulky disease, compared to 9/26 (35%) and 20/26 (77%), respectively, in those who did not receive RT. For our entire cohort, 2-year PFS and OS were 91% and 100%, respectively. For those who had RT, 2-year PFS was 83% compared to 92% in those who did not need RT. There was a total of 3 relapses (9%) at last follow up with 1/7 (14%) in those who had RT vs. 2/26 (8%) in those without RT. For the patient who relapsed after RT, relapse occurred both at initial and new sites. For the 2 who relapsed who did not receive RT, 1 was both in initial and new sites, while the other was initial site only.

CONCLUSION

At our institution, the majority of patients treated per EuroNet-PHL-C1 avoided RT with excellent outcomes. For those requiring RT, limiting RT to only sites of IR at ERA does not appear to adversely affect outcomes, though analysis is limited by the low number of failures.

Phase I Trial of 'Re-Priming' Radiation Therapy for Relapsed/Refractory Non-Hodgkin Lymphoma Patients in Incomplete Response after Chimeric Antigen Receptor T-Cell (CAR-T) Therapy

PURPOSE/OBJECTIVE(S)

Inpatients with relapsed/refractory non-Hodgkin lymphoma (R/R NHL) treated with CD19-directed CAR-T, only ∼40% achieve complete response (CR) by day 30 PET/CT evaluation. Of those who do not, the large majority (∼70%) ultimately fail, providing an ideal target for early therapeutic intervention to 're-prime' CAR-T. Preclinical and early clinical studies suggest potential synergy and immune augmentation when combining RT with CAR-T. Here we report the phase I results of a prospective phase I/II clinical trial hypothesizing that early salvage focal RT to poor responding sites of disease after CAR-T in R/R NHL patients is safe (phase I) and will improve conversion to CR by day 90 post-CAR-T PET/CT from 29% (historical control) to 58% (phase II).

MATERIALS/METHODS

Weopened a single-arm open-label phase I/II prospective clinical trial at our institution for R/R NHL patients treated with CD19-directed CAR-T with incomplete response on day 30 post-CAR-T PET/CT scan (defined as Lugano > = 4). The phase I component used a 'Rolling 6' design with 6 patients enrolled concurrently at the "definitive" dose level (40-50 Gy EQD2 [i.e., 30 Gy in 5 fractions], with de-escalation to "palliative" dose level (20-32.5 Gy EQD2 [i.e., 20 Gy in 5 fractions]) if >2 dose-limiting toxicities (DLT) observed. Hypofractionated regimens (i.e., 5 fractions) directed only to residual FDG-avid disease were recommended to minimize lymphopenia and potentially result in a more favorable immune microenvironment. DLT rate was defined within 60 days of RT by CTCAE v5.0 grade 4+ hematologic, grade 3+ dermatitis/burn, pneumonitis, enteritis, or other toxicity attributable to RT, as well as new grade 3+ cytokine release syndrome (CRS) per ASTCT consensus guidelines or grade 3+ neurotoxicity per ASTCT ICANS consensus guidelines for adults.

RESULTS

BetweenApril 2021 and July 2022, 6 patients were enrolled. All 6 patients had diffuse large B-cell lymphoma (DLBCL), with 3/6 (50%) transformed from low-grade follicular lymphoma. 2/6 had primary refractory DLBL, while the other 4/6 had median 2.5 lines of treatment prior to CAR-T. No patient had prior RT to a site of residual FDG-avid disease on day 30 post-CAR-T PET/CT. 5/6 patients were treated to 30 Gy in 5 fractions, with the remainder patient treated to 36 Gy in 10 fractions. No grade 3+ DLTs related to RT were observed in the 60-day post-RT period. RT related toxicities included grad 1 alopecia, grade 1 radiation pneumonitis, grade 1 nausea & vomiting, and grade 2 skin infection.

CONCLUSION

Early salvage focal "definitive" dose RT to sites of incomplete response on day 30 post-CAR-T PET/CT for R/R/ NHL patients was safe with no de-escalation of dose needed. This dose will used in the subsequent phase II component of the trial.

The Changing Profile of Academic Radiation Oncology Leaders: Updates over the Past Decade

PURPOSE/OBJECTIVE(S)

To report objective characteristics of program directors (PDs) and chairpersons and examine contemporary trends of their demographic and academic profiles from 2013 to 2023. We hypothesize that there are significant changes in the profiles of our radiation oncology leaders over the past decade.

MATERIALS/METHODS

A total of 89 PDs and 85 chairpersons in the Accreditation Council for Graduate Medical Education (ACGME)-approved residency programs in the U.S were queried for analysis. Demographic data on race, ethnicity, post graduate training, years in practice were obtained from publicly available online resources (e.g., institutional websites and online networking services for physicians). Variables on academic productivity and professional accolades included Hirsh-index, National Institute of Health (NIH) research grant (R), the ASTRO fellowship designation, and leadership positions in professional society meetings. Descriptive analyses, including Fisher's exact tests, were performed to compare findings from the published article in 2013 on this topic (Wilson LD et al. IJROBP 2013).

RESULTS

A total of 36 out of 89 PDs (40.4%) and 11 out of 85 chairpersons (12.8%) were females, revealing higher proportion of females from the initial analysis: 40.4 vs. 24.1% for PDs (p = 0.025) and 12.8 vs. 9.2% for chairpersons (p = 0.618). 29 out of 89 (32.6%) PDs and 30 out of 85 (35.3%) chairpersons were non-White. The median length of practice for PDs and chairpersons were 11 and 29 years, respectively. 38 out of 89 PDs (42.7%) and 11 out of 85 (12.9%) chairpersons were employed at the institution of their training. 7 out of 89 (7.9%) for PDs and 51 out of 85 (60.0%) for chairpersons were awarded FASTRO designation. Median H-index showed increasing trends for PDs (14.5 vs 9) and chairpersons (40 vs 29) from the initial analysis.

CONCLUSION

While most PDs and chairpersons are males, female representation has increased in radiation oncology leadership in the last 10 years, most notably among PDs. Academic productivity among our leaders has also increased. These trends highlight the changes in the landscape of our leadership characteristics.

Effect of Moringa oleifera seed flour on the rheological, physico-sensory, protein digestibility and fatty acid profile of cookies

In the present study, debittered Moringa Oleifera seed flour (DDMF) rich in protein, vitamins, minerals and balanced amino acid and fatty acid profile was used to develop functional cookies. DDMF was incorporated at 25, 50, 75 and 100% levels and studied their effect on flour rheological, physicochemical, micro-structural, sensory and nutritional properties of cookies. The results revealed that the addition of an increasing amount of DDMF from 0 to 100% increased water absorption (59.5-77%) by farinograph study; cookie dough hardness (89.2-284.7 N); decreased pasting temperature (60.2-30.1 °C) and peak viscosity (696-9 BU) by amylograph study. SEM studies of cookies indicated that, in control cookies, starch granules are completely gelatinized and enmeshed in the gluten protein matrix, whereas, in 50% DDMF incorporated cookies, partially gelatinized starch granules are seen embedded in a weak protein matrix. Sensory evaluation showed that incorporating DDMF, up to 50% of cookies had clean mouthfeel without any residue formation and were highly acceptable; however, beyond that limit, they became brittle. The addition of 50% DDMF increased cookies' in-vitro protein digestibility, mineral contents, and fatty acids content. Thus, the nutritional quality of cookies concerning quantity and quality of protein and fat could be enhanced by incorporating DDMF.

Low carbohydrate high fat flour: its rheology, bread making, physico-sensory and staling characteristics

A low carbohydrate and high fat (LCHF) flour was developed by combining almond flour, desiccated coconut flour, defatted soya flour, dry gluten powder, psyllium husk and skimmed milk powder. Determination of rheological, bread making, nutritional, and staling characteristics of LCHF flour in comparison with wheat flour (WF) was studied. The results showed that LCHF flour had lower amylograph pasting temperature (31.6 °C), peak viscosity (200 BU), farinograph dough stability (0.8 min), and bread volume (315 ml) compared to WF (61.0 °C; 782 BU; 8.7 min; and 525 ml) respectively. The use of additive mixes such as fungal alpha-amylase, sodium stearoyl-2-lactylate and xanthan gum, improved the volume and texture of the LCHF bread. Scanning electron microscope images showed little or no presence of starch granules in LCHF dough and bread. Differential scanning calorimetry studies indicated that, during storage (1-5 days), the enthalpy for gelatinization of endotherm starch increased (0.71-3.40 j/g) in WF bread, however, in LCHF bread this increase was lesser (0.53 to 2.2 j/g) indicating slower staling rate in LCHF bread. The LCHF bread showed lower carbohydrate (13.7%), in-vitro starch digestibility (17.3%) and staling rate, higher protein (22.51%), fat (11.01%), and medium-chain fatty acids than WF bread (51.9%; 38.2%; 12.57%; 3.78%) respectively. The results showed that the developed product would be beneficial for people suffering from diabetics and obesity.

Effect of fat and sugar replacement on rheological, textural and nutritional characteristics of multigrain cookies

Fat and sugar are responsible for the structure of cookies but make them nutritionally inferior. Therefore, in the present study, cookies with improved nutrition using whole wheat flour (WWF) and incorporation of multigrain mix (MM-oats, peas and fenugreek flours) at 0, 25, 50, 75 and 100% levels was studied. Further, fat was replaced using pumpkin seed (PS) or watermelon seed (WS) at 25, 50 and 75% level and sugar was replaced using dry dates (DD) or raisins (RS) separately at 20, 40 and 60%. MM having protein at 15.13% and dietary fibre at 12.83% significantly decreased the water absorption (68.1-60.6%), stability (2.52-1.35 min), amylograph peak viscosity (665-821 BU), and cookie dough hardness (1737-690.5) at 100% MM. Based on the physico-sensory analysis, 75% replacement of WWF with MM was selected for replacement of fat or sugar. Addition of PS or WS increased the dough hardness (1235-4103 g), whereas the spread ratio of cookies decreased from 6.25 and 6.31 to 5.54 and 4.06 respectively. Replacement of fat with PS at 50%, sugar by DD at 40% along with a combination of sodium stearoyl lactylate (SSL) and glycerol mono stearate (GMS) showed improvement in the cookie texture. The scanning electron microscope (SEM) of cookie showed coating of starch granules and appearance of sheet-like covering of protein network. The mono and polyunsaturated fatty acid profile of cookies improved apart from a two-fold increase in protein and three-fold increase in dietary fibre.

Rheological, physico-sensory and antioxidant properties of punicic acid rich wheat bread

Punicic acid (PA), a predominant fatty acid (85%) in pomegranate seeds, also called as an ω-5 fatty acid, is known to render various health beneficial effects to humans. The objective of this study was to prepare and observe the effect of replacement of wheat flour with 5-12.5% punicic acid rich pomegranate seed powder (PSP, 9XXX fraction) on rheological, physico-sensory and antioxidant properties of bread. The increasing amount of PSP caused decrease in farinograph water absorption capacity, dough stability; amylograph peak viscosity; bread volume and overall quality score, whereas crumb hardness was increased. The combination of additives (CA) showed significant improvement in dough strength, texture and quality of bread with 10% PSP. The total polyphenol content (TPP) and radical scavenging activity (RSA) increased by 10- to 30-fold while PA was increased to 60-fold when compared to control. The recovery of PA from bread samples was in range of 45-60% and further increased by the addition of CA (65%). Hence, 10% PSP bread having 60% recovery of PA can be successfully considered for formulations without altering the rheological and sensory quality of bread. These results reveal that PA rich PSP prepared from a fruit industry by-product can be utilized for preparing antioxidant rich functional bread which also helps in overall improvement of bone health.

Influence of multigrain premix on nutritional, in-vitro and in-vivo protein digestibility of multigrain biscuit

Effect of addition of multigrain premix (MGP) prepared using a combination of cereals, pulses and oilseeds at 40% level, on nutritional properties of multigrain biscuit, its in-vitro and in-vivo protein digestibility and protein profiling were studied. The incorporation of MGP significantly increased the protein content (from 7.37 to 16.61%), insoluble dietary fiber (from 1.71 to 6.67%), soluble dietary fiber (from 0.46 to 2.42%). The significant increase in the levels of isoleucine (ND-34.79%), methionine (0.04 to 7.65%), tryptophan (0.22 to 5.95%) valine (0.38 to 16.58%), lysine (0.36 to 7.32%), and threonine (0.51 to 7.2%) was observed, whereas fatty acid profile of MGP incorporated biscuits showed increased polyunsaturated fatty acids and decreased saturated fatty acids. The vitamin-mineral profile of MGP incorporated biscuits showed increased the thiamin (0.07-0.21 mg/100 g), riboflavin (0.09-0.28 mg/100 g), calcium (12.89-45.28 mg/100 g) and iron (1.13-3.47 mg/100 g) contents. The in-vitro protein digesibility of multigrain and control biscuits indicated that the proteins present in multigrain biscuits had high digestibility (71.73%) as compared to control biscuit (38.13%). The in-vivo studies indicated that, the protein quality of multigrain biscuits was comparable with casein protein with high protein efficiency ratio of 3.02. The electrophoretic pattern of multigrain biscuits showed subunit molecular weight distribution of different protein units and aggregation of protein bands at high molecular weight region of 85 to 166 kD. The outcome of the study indicated the possibility of utilising MGP to improve the overall nutritional quality of biscuits.

Reliability and validity of PHQ-9 when administered by health workers for depression screening among women in primary care

BACKGROUND

Depression is twice more prevalent among women but remains unidentified in primary care.

OBJECTIVE

We aimed to estimate the reliability and validity of PHQ-9, when administered by health workers, a cadre of public health staff, posted in primary health centres. We translated PHQ-9 to Malayalam, a language spoken by 30 million people in Kerala, India. Health workers administered PHQ-9 to women (n = 238) aged 18-60 years in a high prevalent primary care setting. Mini International Neuropsychiatric Interview (MINI) was administered by the psychiatrist on the same day to diagnose depressive disorder. Two health workers administered PHQ-9, independently, in a subset of 21 women.

RESULTS

The internal consistency reliability (Cronbach's alpha 0.89) and inter-rater reliability (intra class correlation coefficient, 0.94; 95% CI, 0.86-0.95) were high. On ROC analysis, area under curve was 0.92 (95% CI 0.88-0.96). For a cut-off score of ≥9, PHQ-9 had a sensitivity of 82.5%, (95% CI, 72.4-92.6), specificity of 90.1% (95% CI, 84.5-95.6%), positive predictive value of 73.4% (95% CI, 62.4-84.4%) and negative predictive value of 93.9% (95% CI, 90.2-97.6%). The accuracy was 88.2% (84.0-92.4%) and positive likelihood ratio was 8.3. Factor analysis supported a single factor, with eigen value above 1, with high loading for all items (0.73-0.79), except item related to appetite (0.58). This explained 62% of variance in the data. Prevalence of MINI diagnosed depressive disorders was 25%.

CONCLUSION

When administered by health workers, PHQ-9 has good reliability and at cut off score ≥9, it has good validity to identify depression in primary care.

Minimally Differentiated Acute Myeloid Leukemia: A Morphologic, Cytochemical and Ultrastructural Study

Seven of 368 cases of acute myeloid leukemia (AML) could not be subclassified by routine morphologic, cytochemical and immunologic analyses during the period January 1989 to December 1990. Further investigations including ultrastructural examination, anti-myeloperoxidase and myeloid specific antigen analysis were carried out in all these patients and they were classified as AML-MO, as per the FAB criteria. Morphologically these blasts resembled ALL-L2/AML-M1. Cytochemlcally they were negative for Sudan black, myeloperoxidase, periodic acid-Schiff, and non-specific esterase. On initial immunophenotypic analysis, they could not be classified Into B, T or myeloid lineages. Further investigations revealed CD13 and CD33 positivity in 4 of 6 patients. Anti-myeloperoxidase was positive in 6 of 6 patients and ultrastructural examination revealed myeloperoxidase-positive blasts in 6 of 7 cases. Cytogenetic analysis done in one patient revealed 60 % abnormal metaphases. Six of 7 cases were treated with aggressive chemotherapy. One patient achieved complete remission but relapsed after 6 months, whereas others were resistant to treatment. Hence we conclude that an aggressive investigative and therapeutic approach is required to identify and treat AML-MO.

Development of multigrain premixes-its effect on rheological, textural and micro-structural characteristics of dough and quality of biscuits

Four different Multigrain Premixes (MGPs) namely MGP I, MGP II, MGP III, MGP IV were developed to select the best premix for preparation of biscuits based on nutritional value and biscuit quality. The MGPs were prepared using cereals (barley, sorghum, maize, oats), pulses (chickpea dhal, green gram, peas, soya flour), millets (pearl millet, finger millet) and wheat germ each at 20 % level. The MGPs developed had 22.91-27.84 % protein, 16.82-18.72 % dietary fiber and 3.11-3.46 % minerals. The wheat flour was replaced with MGPs separately at different levels of 10, 20, 30, 40 and 50 %. The incorporation of these MGPs significantly (p ≤ 0.05) decreased the water absorption (56.0-50.9 %), peak viscosity (273.67-154.92 RVU), biscuit spread ratio (10.28-8.15) and increased the pasting temperature (67.10-79.20 °C), dough hardness (311.66-460.26 N) and biscuit breaking strength (13.25-28.68 N). SEM studies showed that incorporation of MGP disrupted the protein matrix. Among the MGPs, MGP III was found to be more suitable even at the 40 % level for obtaining nutritious multigrain biscuits with higher protein, dietary fiber, and mineral content.

Variations in the cone packing density with eccentricity in emmetropes

AIM

To describe the parafoveal cone arrangement in emmetropic subjects and its variations with eccentricity, meridians and change in axial length in Indian eyes.

METHODS

We imaged 25 subjects using compact adaptive optics (AO) retinal camera prototype, the rtx1. Imaging was done at 1, 2, and 3° eccentricity from the fovea in four meridians: nasal, temporal, superior, and inferior.

RESULTS

A statistically significant drop in the cone packing density was observed from 2 to 3° (2° eccentricity=25 350/mm(2) (5300/mm(2), 8400-34 800/mm(2)) 3° eccentricity=20 750/mm(2) (6000 mm(2), 9000-33 670/mm(2))) P<0.05. The spacing correspondingly increased with increase in distance from the fovea (2° eccentricity=6.9 μm (0.70 μm, 5.95-11.6 μm)) and 3°eccentricity=7.80 μm (1.00 μm, 6.5-13.5 μm) P<0.05. As the axial length increases, the cone density significantly decreases. Interocular variations were noted.

CONCLUSION

With the advent of AO, visualization at the cellular level is now possible. Understanding the photoreceptor mosaic in the parafoveal space in terms of its density, spacing, and arrangement is crucial so as to detect early pathology and intervene appropriately. Newer therapeutic modalitites that are targeted at the cellular level like yellow micropulse laser, stem cells, gene therapy and so on may be better monitored in terms of safety and efficacy.

Antioxidant and antimicrobial activities of Bauhinia racemosa L. stem bark

The present study was carried out to evaluate the antioxidant and antimicrobial activities of a methanol extract of Bauhinia racemosa (MEBR) (Caesalpiniaceae) stem bark in various systems. 1,1-Diphenyl-2-picryl-hydrazyl (DPPH) radical, superoxide anion radical, nitric oxide radical, and hydroxyl radical scavenging assays were carried out to evaluate the antioxidant potential of the extract. The antioxidant activity of the methanol extract increased in a concentration-dependent manner. About 50, 100, 250, and 500 microg MEBR inhibited the peroxidation of a linoleic acid emulsion by 62.43, 67.21, 71.04, and 76.83%, respectively. Similarly, the effect of MEBR on reducing power increased in a concentration-dependent manner. In DPPH radical scavenging assays the IC50 value of the extract was 152.29 microg/ml. MEBR inhibited the nitric oxide radicals generated from sodium nitroprusside with an IC50 of 78.34 microg/ml, as opposed to 20.4 microg/ml for curcumin. Moreover, MEBR scavenged the superoxide generated by the PMS/NADH-NBT system. MEBR also inhibited the hydroxyl radical generated by Fenton's reaction, with an IC50 value of more than 1000 microg/ml, as compared to 5 microg/ml for catechin. The amounts of total phenolic compounds were also determined and 64.7 microg pyrocatechol phenol equivalents were detected in MEBR (1 mg). The antimicrobial activities of MEBR were determined by disc diffusion with five Gram-positive, four Gram-negative and four fungal species. MEBR showed broad-spectrum antimicrobial activity against all tested microorganisms. The results obtained in the present study indicate that MEBR can be a potential source of natural antioxidant and antimicrobial agents.

Antibacterial potential of an antispasmodic drug dicyclomine hydrochloride

BACKGROUND & OBJECTIVES

Several compounds are known to possess antimicrobial activity in addition to their predesignated pharmacological actions. In the present study, dicyclomine hydrochloride, an antispasmodic drug, was tested for possible antimicrobial property in vitro and in vivo.

METHODS

The minimum inhibitory concentration (MIC) of dicyclomine against the bacteria was determined by agar and broth dilution methods in vitro. The antibacterial activity of dicyclomine was confirmed by animal experiments. Toxicity and protective efficacy of the drug were tested in vivo.

RESULTS

Dicyclomine inhibited most of the bacterial isolates tested at 25-100 microg/ml concentration, and a few were sensitive even at a lower concentration (10 microg/ml). Dicyclomine was found to be bacteriostatic in nature against Shigella dysenteriae 7, and bactericidal against S. aureus NCTC 6571, 8530, and 8531. When administered to Swiss white mice at doses of 30 and 60 microg/mouse, dicyclomine protected the animals challenged with 50 MLD of Salmonella typhimurium NCTC 74.

INTERPRETATION & CONCLUSION

Dicyclomine showed inhibitory action against several pathogenic bacteria. It also offered significant protection to mice against the bacterial challange. As dicyclomine is in routine therapeutic use, it may be developed as a potent antimicrobial agent in many infections.

Evaluation of in vitro and in vivo antibacterial activity of dobutamine hydrochloride

PURPOSE

To determine the in vitro and in vivo antibacterial activity of a cardiovascular drug dobutamine hydrochloride.

METHODS

The minimum inhibitory concentration (MIC) of dobutamine was determined both by agar and broth dilution methods against 331 strains of bacteria from three gram positive and 13 gram negative genera. The antibacterial action of dobutamine was further tested in animal models.

RESULTS

Dobutamine was seen to possess powerful inhibitory action (5-200mg/mL) against most test bacteria in in vitro studies. It was bacteriostatic in nature. In vivo studies showed that the drug offered significant protection (p< 0.001) to mice challenged with a virulent bacterium.

CONCLUSION

Dobutamine showed remarkable antibacterial property against several pathogenic bacteria. Its potential as an antibacterial agent may be confirmed after further pharmacological studies.

Characterization of toxin from cheilanthes fern and its effect on lymphocyte proliferation and DNA fragmentation

Thin layer chromatography of aqueous extract of whole Cheilanthesfarinosa fern indicated the presence of ptaquiloside or ptaquiloside like compound, coinciding Rf values with that of Pterosin B standard. HPLC analysis revealed the presence of 26.3 mg/kg ptaquiloside. In vitro studies of the aqueous extract on lymphocyte culture revealed a correlation between stimulative indices and concentration of aqueous extract. Stimulation in lymphocyte proliferation was in order of bracken > cheilanthes > ConA> ptaquiloside standard. On incubation of lymphocyte with aqueous extract of ferns, no DNA damage was observed in isolated DNA.

The discovery of a potent, intracellular, orally bioavailable, long duration inhibitor of human neutrophil elastase--GW311616A a development candidate

The discovery of a potent intracellular inhibitor of human neutrophil elastase which is orally active and has a long duration of action is described. The pharmacodynamic and pharmacokinetic properties of a trans-lactam development candidate, GW311616A, are described.

A new phorbol diester from Aleurites moluccana

A new phorbol diester, 13-O-myristyl-20-O-acetyl-12-deoxyphorbol (1), has been isolated from the benzene extract of the heartwood of Aleurites moluccana. In addition, hentriacontane, 6,7-dimethoxycoumarin, 5,6,7-trimethoxycoumarin and beta-sitostenone are being reported for the first time from this species.

Intracellular inhibition of human neutrophil elastase by orally active pyrrolidine-trans-lactams

Described are the acylation binding of trans-lactam 1 to porcine pancreatic elastase, the selection of the SO2Me activating group for the lactam N which also confers metabolic stability in hamster liver microsomes, the introduction of aqueous solubility through the piperidine salt 9, the in vivo oral activity of 9 and its bioavailability, and the introduction of 9 as an intracellular neutrophil elastase inhibitor.

Solitary coherent structures in viscoelastic shear flow: computation and mechanism

Starting from stationary bifurcations in Couette-Dean flow, we compute nontrivial stationary solutions in inertialess viscoelastic circular Couette flow. These solutions are strongly localized vortex pairs, exist at arbitrarily large wavelengths, and show hysteresis in the Weissenberg number, similar to experimentally observed "diwhirl" patterns. Based on the computed velocity and stress fields, we elucidate a heuristic, fully nonlinear mechanism for these flows. We propose that these localized, fully nonlinear structures comprise fundamental building blocks for complex spatiotemporal dynamics in the flow of elastic liquids.

Dactuliophora Leaf Spot of Pearl Millet in Niger and Mali

Pearl millet (Pennisetum glaucum (L.) R. Br.) fields and cultivar trials in Sadoré, Niger, and Samanko, Mali, were surveyed in late August 1999 Most plants were in the late stem elongation to panicle exertion stage Local open-pollinated cultivars, experimental hybrids, and inbreds had disease severities of up to 10% of foliage diseased, with most severe disease on lower leaves. Individual, young, brown necrotic lesions averaged 2 × 1 mm and were surrounded by circular to irregular purple watersoaked margins 1 to 7 mm wide. Lesions expanded in irregular concentric rings, with zones of necrosis often separated by zones of green tissue Mature, individual lesions averaged 4.3 × 1.9 cm. Entire leaves could be blighted by coalescing lesions. No sclerotia were observed in young lesions, but sclerotia consistently developed and were macroscopically visible in necrotic tissues of older lesions. Sclerotia were oblong to pyriform (averaging 178 × 124 mm) and borne on erumpent, cup-shaped sclerotiophores. When incubated under high humidity, sterile gray mycelia grew rapidly from necrotic lesions up to a distance of ≈5 mm on the lower leaf surface, which likely resulted in the large concentric zones necrosis. Fungal characteristics and symptoms were consistent with disease caused by Dactuliophora elongata Leakey (1,2). Based on observations at the International Pearl Millet Downy Mildew Virulence Nursery in Mali, it is likely that resistance to D. elongata exists. Leaf spot of pearl millet caused by D. elongata has been reported only in Nigeria (1,2). Our observations confirm that the pathogen also is present on pearl millet Niger and Mali. References: (1) C. L. A. Leakey. Trans. Br. Mycol. Soc. 47:341, 1964. (2) P. D. Tyagi Proc. Ind. Acad. Sci. (Plant Sci.) 94:407, 1985.

Characterization of the DNA-binding domain of beta protein, a component of phage lambda red-pathway, by UV catalyzed cross-linking

beta protein, a key component of Red-pathway of phage lambda is necessary for its growth and general genetic recombination in recombination-deficient mutants of Escherichia coli. To facilitate studies on structure-function relationships, we overexpressed beta protein and purified it to homogeneity. A chemical cross-linking reagent, glutaraldehyde, was used to stabilize the physical association of beta protein in solution. A 67-kDa band, corresponding to homodimer, was identified after separation by SDS-polyacrylamide gel electrophoresis. Stoichiometric measurements indicated a site-size of 1 monomer of beta protein/5 nucleotide residues. Electrophoretic gel mobility shift assays suggested that beta protein formed stable nucleoprotein complexes with 36-mer, but not with 27- or 17-mer DNA. Interestingly, the interaction of beta protein with DNA and the stability of nucleoprotein complexes was dependent on the presence of MgCl2, and the binding was abolished by 250 mM NaCl. The Kd of beta protein binding to 36-mer DNA was on the order of 1.8 x 10(-6) M. Photochemical cross-linking of native beta protein or its fragments, generated by chymotrypsin, to 36-mer DNA was performed to identify its DNA-binding domain. Characterization of the cross-linked peptide disclosed that amino acids required for DNA-binding specificity resided within a 20-kDa peptide at the N-terminal end. These findings provide a basis for further understanding of the structure and function of beta protein.

Case report: renal scintigraphy in the diagnosis of urinary extravasation

Renal scintigraphy is a sensitive method for disclosing urinary extravasation. Its role following a road traffic accident is clearly presented in this case report. It is concluded that such a study can fill an important gap between the clinical and intravenous urography assessment and the more invasive studies in trauma victims.

DNA-induced conformational changes in RecA protein. Evidence for structural heterogeneity among nucleoprotein filaments and implications for homologous pairing

We have used circular dichroism as a probe to characterize the solution conformational changes in RecA protein upon binding to DNA. This approach revealed that RecA protein acquires significant amounts of alpha-helix upon interaction with DNA. These observations, consistent with the data from crystal structure (Story, R. M., Weber, I., and Steitz, T. (1992) Nature 355, 318-325), support the notion that some basic domains including the DNA binding motifs of RecA protein are unstructured and might contribute to the formation of alpha-helix. A comparison of nucleoprotein filaments comprised of RecA protein and a variety of DNA substrates revealed important structural heterogeneity. The most significant difference was observed with poly(dG). poly(dC) and related polymers, rich in GC sequences, which induced minimal amounts of alpha-helix in RecA protein. The magnitude of induction of alpha-helix in RecA protein, which occurred concomitant with the production of ternary complexes, was 2-fold higher with homologous than heterologous duplex DNA. Most importantly, the stimulation of ATP hydrolysis by high salt coincided with that of the induction of alpha-helix in RecA protein. These conformational differences provide a basis for thinking about the biochemical and structural transitions that RecA protein experiences during the formal steps of presynapsis, recognition, and alignment of homologous sequences.

Use of structure-directed DNA ligands to probe the binding of recA protein to narrow and wide grooves of DNA and on its ability to promote homologous pairing

We have used circular dichroism and structure-directed drugs to identify the role of structural features, wide and narrow grooves in particular, required for the cooperative polymerization, recognition of homologous sequences, and the formation of joint molecules promoted by recA protein. The path of cooperative polymerization of recA protein was deduced by its ability to cause quantitative displacement of distamycin from the narrow groove of duplex DNA. By contrast, methyl green bound to the wide groove was retained by the nucleoprotein filaments comprised of recA protein-DNA. Further, the mode of binding of these ligands and recA protein to DNA was confirmed by DNaseI digestion. More importantly, the formation of joint molecules was prevented by distamycin in the narrow groove while methyl green in the wide groove had no adverse effect. Intriguingly, distamycin interfered with the production of coaggregates between nucleoprotein filaments of recA protein-M13 ssDNA and naked linear M13 duplex DNA, but not with linear phi X174 duplex DNA. Thus, these data, in conjunction with molecular modeling, suggest that the narrow grooves of duplex DNA provide the fundamental framework required for the cooperative polymerization of recA protein and alignment of homologous sequences. These findings and their significance are discussed in relation to models of homologous pairing between two intertwined DNA molecules.

Idiopathic hypereosinophilic syndrome presenting as childhood hemiplegia

A case of childhood hemiplegia due to idiopathic hypereosinophilic syndrome is reported. There was no cardiac lesion. The neurological complications associated with hypereosinophilic syndrome and the pathophysiological mechanism of neurotoxicity of human eosinophils are discussed. It is likely that the neurological deficit was due to eosinophilic neurotoxicity.

Haemodialysis-related porphyria cutanea tarda and treatment by recombinant human erythropoietin

Haemodialysis-related porphyria cutanea tarda is a rare, but serious and mutilating skin condition, resulting from extremely high plasma porphyrin levels because of their inadequate clearance by haemodialysis. The treatment is very difficult as chloroquine is ineffective and venesection, the conventional treatment of this disease, is not always an option because of anaemia of end-stage renal disease. We report a case of haemodialysis-related porphyria cutanea tarda and her successful management by recombinant human erythropoietin treatment.

Clinico-pathological profile of lymphomas in south India: a prospective rural referral hospital study of 103 cases

A prospective clinical and histopathological study of 103 patients with lymphomas is reported. Of these, 72 (69.9%) had non-Hodgkin's lymphoma (NHL) and 31 (30.1%) had Hodgkin's lymphoma (HL). The median age at presentation was 34 and 43 years for Hodgkin's and non-Hodgkin's lymphoma respectively, which is lower than that seen in the West. Fever and superficial lymphadenopathy were the commonest presenting features and 'B' symptoms were present in over 60% of both groups. Seventy-five per cent of NHL and 64.5% of HL presented in stages III and IV of the disease.

A microcomputer program to analyze the CD spectrum of proteins and nucleic acids--use of LOTUS 1-2-3 spread sheet

A user friendly interactive computer program, CIRDIC, is developed which calculates the molar ellipticity and molar circular dichroic absorption coefficients from the CD spectrum. This, in combination with LOTUS 1-2-3 spread sheet, will give the spectra of above parameters vs wavelength. The code is implemented in MicroSoft FORTRAN 77 which runs on any IBM compatible PC under MSDOS environment.

Effect of yoga on exercise tolerance in normal healthy volunteers

Twelve normal healthy volunteers (6 males and 6 females) undergoing yoga training for 90 days were studied for the effect of yoga on exercise tolerance. Their ages ranged from 18 to 28 years. The volunteers were taught only Pranayama for the first 20 days and later on yogic asanas were added. Sub-maximal exercise tolerance test was done on a motorized treadmill by using Balke's modified protocol, initially, after 20 days (Phase-I) and after 90 days of yoga training (Phase-II). Pyruvate and lactate in venous blood and blood gases in capillary blood were estimated immediately before and after the exercise. Minute ventilation and oxygen consumption were estimated before and during the test. Post exercise blood lactate was elevated significantly during initial and Phase-I, but not in Phase-II. There was significant reduction of minute ventilation and oxygen consumption only in males in Phase-I and II at the time when the volunteers reached their 80% of the predicted heart rate. Female volunteers were able to go to higher loads of exercise in Phase-I and II.