Optical bleaching front in bedrock revealed by spatially-resolved infrared photoluminescence

Optically stimulated luminescence (OSL) dating of sediment, based on the accumulation of trapped charge in natural crystals since their last exposure to daylight, has revolutionised our understanding of the late Quaternary period. Recently, a complementary technique called luminescence rock surface dating (RSD), which uses differential spatial eviction of trapped charges in rocks exposed to daylight, has been developed to derive exposure and burial ages, and hard-rock erosion rates. In its current form, the RSD technique suffers from labour intensive sample preparation, uncertainties in the depth and dose rate estimates, and poor resolution of the luminescence-depth profile. Here, we develop a novel, 2D luminescence imaging technique for RSD of large rock slabs (3 × 5 cm) to overcome these challenges. We utilize the recently discovered infrared photoluminescence (IRPL) signal for direct, non-destructive imaging of the luminescence-depth profile in a sub-aerially exposed granitic rock, with an unprecedented spatial resolution of ~140 µm. We further establish a correlation between luminescence and geochemistry using micro X-ray fluorescence (µXRF) spectroscopy. Our study promises a substantial advancement in luminescence imaging and paves the path towards novel applications using 2D dating, micro-dosimetry in mixed composition samples, and portable instrumentation for in-situ luminescence measurements.

Identification and Characterization of Menadione and Benzethonium Chloride as Potential Treatments of Pierce's Disease of Grapevines

Xylella fastidiosa infects a wide range of plant hosts and causes Pierce's disease (PD) of grapevines. The type 1 multidrug resistance (MDR) efflux system is essential for pathogenicity and survival of bacterial pathogens in planta. X. fastidiosa, with a single MDR system, is significantly more vulnerable to inhibition by small-molecule treatments than most bacterial pathogens that typically carry redundant MDR systems. A high-throughput cell viability assay using a green fluorescent protein-marked strain of X. fastidiosa Temecula 1 was developed to screen two Prestwick combinatorial small-molecule libraries of drugs and phytochemicals (1,600 chemicals in total) approved by the Food and Drug Administration and European Medicines Agency for cell growth inhibition. The screens revealed 215 chemicals that inhibited bacterial growth by >50% at 50 µM concentrations. Seven chemicals proved to lyse X. fastidiosa cells at 25 µM, including four phytochemicals. Menadione (2-methyl-1,4-naphthoquinone, vitamin K) from the phytochemical library and benzethonium chloride (a topical disinfectant) from the chemical library both showed significant bactericidal activity against X. fastidiosa. Both menadione and benzethonium chloride foliar spray (15 and 5 mM, respectively) and soil drench (5 and 25 mM, respectively) treatments were equally effective in reducing PD symptoms by 54 to 59% and revealed that the effects of both chemical treatments became systemic. However, menadione was phytotoxic when applied as a foliar spray at effective concentrations, causing significant loss of photosynthetic capacity.

Two-minute versus 6-minute walk distances during 6-minute walk test in neuromuscular disease: Is the 2-minute walk test an effective alternative to a 6-minute walk test?

Functional tests such as Motor Function Measure-32 (MFM-32), supine to stand, ascend/descend stairs permit the assessment of task-specific motor function in neuromuscular disease (NMD). The 6-min walk test (6MWT), though functional, is primarily used to assess endurance and disease progression in children with neuromuscular disorders. Barriers to 6MWT administration, in this population, can include reduced attention span due to age and inability to tolerate test length due to weakness. We propose task-specific functional deficits are related to endurance. Additionally, the 2-min walk test (2MWT) could effectively replace the 6MWT in this population. Seventy-seven participants, ages 5-18, with a variety of neuromuscular disorders performed the 6MWT, timed functional tests (TFT), and the MFM-32. Correlation and paired t-test analyses were used to compare the distance walked in the first 2 min (2MWD) to the distance walked in the entire 6 min (6MWD) and to the functional outcome measures above. The 2MWD strongly correlated with 6MWD and the other outcome measures. Paired t-test analysis also showed that the 2MWD did not differ from the distance walked in the last 2 min of the 6MWT. Although equivalence testing could not reject the claim that this difference exceeded the upper practical limit of 9.5 m, it only showed a modest overestimation of the 4-6MWD compared with the 2MWD. Together, our results support the ability of the 2MWD to predict the 6MWD, specifically in the pediatric neuromuscular disease population.

Chicago Classification normative metrics in a healthy Indian cohort for a 16-channel water-perfused high-resolution esophageal manometry system

BACKGROUND

High-resolution esophageal manometry (HREM) interpretation by the Chicago Classification (CC) derives its normal values from western volunteers using solid-state catheters. There is no normative data for the 16-channel water-perfused HREM system commonly used in India.

AIMS

To determine normal values for a 16-channel water-perfused HREM catheter in supine posture using healthy volunteers and substitute these normal values (if different from CC values) in the CC v3.0 algorithm.

METHODS

After ethics approval and informed consent, 53 volunteers (31 men) with no gastrointestinal (GI) symptoms or medications affecting GI motility underwent HREM by standard protocol. Age, gender, body mass index (BMI), and manometry parameters analyzed using Trace 1.3.3 software were collected. The median, range, and 5, 10, 75, and 95 percentiles (where applicable) were obtained for all HREM metrics. Normal value percentiles were defined as 95th (integrated relaxation pressure [IRP]), 10th-100th (distal contractile integral [DCI]), and minimum (distal latency [DL]).

RESULTS

The mean age was 30 years and the BMI was 24.2 kg m^-2 . Compared to CC, our normal metrics were lower for IRP (13 mm Hg) and DCI (350-4500 mm Hg s cm). DCI >4500 and <70 (<5th percentile) were defined as hypercontractile and failed contraction, respectively. Abnormal DL (<4.5 s) and peristaltic break size (>5 cm) were similar to CC metrics. Applying these metrics, CC diagnoses changed in 15% (8/53) with downgrading of ineffective motility to fragmented peristalsis or normal, due to lower DCI cutoff used.

CONCLUSIONS

This is the first report of normative data for the 16-channel water-perfused system in supine posture. It revealed lower IRP and DCI, necessitating modification of CC cutoffs for this system.

Utility of Oxford Classification in Post-Transplant Immunoglobulin A Nephropathy

BACKGROUND

With increasing graft survival, post-transplant immunoglobulin A nephropathy (IgAN) has emerged as an important cause of chronic graft dysfunction in renal allograft recipients. We studied the clinico-pathological features of post-transplant IgAN regardless of the primary disease. The aim was to study the usefulness of the Oxford classification in predicting survival.

METHODS

Indication graft biopsy specimens (n = 915) were received during a 10-year period; 27 biopsy specimens from 22 patients were diagnosed as IgAN.

RESULTS

Post-transplant IgAN was seen in 2.6% of biopsy specimens. Mean time to occurrence was 71.6 ± 47.6 months (range, 6.8 months to 16 years), occurring most commonly 4 to 8 years after transplant. Associated rejection was present in 4 biopsies; 72.7% (16/22), 91% (20/22), and 31.8% (7/22) presented with rise in serum creatinine, proteinuria, and hematuria, respectively. Four (21%) patients had nephrotic range proteinuria. Mesangial hypercelullarity (M1), endocapillary hypercelullarity (E1), segmental glomerulosclerosis (S1), and tubulo-interstitial fibrosis (T1-2) was present in 36.6%, 22.7%, 54.5%, and 31.8% biopsies, respectively. The most frequent Haas class was III (n = 7; 29.1%), followed by classes IV and I (n = 5; 20.8% each). The 2- and 5-year graft survival rates were 75% and 56%, respectively. High serum creatinine, low estimated glomerular filtration rate, E1 and T lesions, and degree of interstitial inflammation predicted graft survival. Interestingly, percentage (>25%) of segmentally sclerosed glomeruli and not S1 correlated with graft outcome.

CONCLUSIONS

The Oxford MEST scheme is useful in predicting graft survival in post-transplant IgAN. The degree of interstitial inflammation is also an important feature for determining graft outcomes in post-transplant IgAN.

Modulation of δ-Aminolevulinic Acid Dehydratase Activity by the Sorbitol-Induced Osmotic Stress in Maize Leaf Segments

Osmotic stress induced with 1 M sorbitol inhibited δ-aminolevulinic acid dehydratase (ALAD) and aminolevulinic acid (ALA) synthesizing activities in etiolated maize leaf segments during greening; the ALAD activity was inhibited to a greater extent than the ALA synthesis. When the leaves were exposed to light, the ALAD activity increased for the first 8 h, followed by a decrease observed at 16 and 24 h in both sorbitol-treated and untreated leaf tissues. The maximum inhibition of the enzyme activity was observed in the leaf segments incubated with sorbitol for 4 to 8 h. Glutamate increased the ALAD activity in the in vitro enzymatic preparations obtained from the sorbitol-treated leaf segments; sorbitol inhibited the ALAD activity in the preparations from both sorbitol-treated and untreated leaves. It was suggested that sorbitol-induced osmotic stress inhibits the enzyme activity by affecting the ALAD induction during greening and regulating the ALAD steady-state level of ALAD in leaf cells. The protective effect of glutamate on ALAD in the preparations from the sorbitol-treated leaves might be due to its stimulatory effect on the enzyme.

Pattern of mismatch repair protein loss and its clinicopathological correlation in colorectal cancer in North India

BACKGROUND

To determine the mismatch repair (MMR) protein loss in colorectal cancer (CRC) in north Indian patients and its clinicopathological correlation.

METHOD

A prospective study on patients with colorectal cancer from a tertiary level hospital conducted between May 2014 and June 2015. MMR protein loss was determined using immunohistochemistry for MLH1, MSH2, PMS2 and MSH6.

RESULTS

52 patients (38 male and 14 females) of CRC, with median age of 52.5 years who underwent resection form the study group. 18 (35%) patients were < 50 years of age. Family history of malignancy was present in 3 (6 %) patients. A total of 15 (29%) patients had loss of MMR protein of which 7 (46%) were < 50 years. Most common MMR loss was combined loss of MSH2 + MSH6 [6 (11.5%)] followed by isolated loss of PMS2 [5 (9.6%)]. MMR protein loss was more frequent in patients with right side colon cancer [12 (42%)] compared to left [3 (13%)] (p = 0.033). MMR protein loss was seen in 11 (34%) out of 32 patients fulfilling the revised Bethesda criteria compared to 4 (20%) out of 20 patients who did not fulfil the criteria (p = 0.352).

CONCLUSION

This study demonstrates high frequency of MMR protein loss in colorectal cancer in north Indian patients which was more common in right colon cancer. Many patients having MMR protein loss do not satisfy the revised Bethesda criteria and would have been missed if selective testing was done. Further research and larger studies are required to validate these findings and develop India specific clinical criteria.

Abstract P4-10-21: Disparities in the risk of mortality in breast cancer based on health insurance status

In 2007 Foley et al showed that low-income Canadian residents had a survival advantage over low-income US residents, which was attributed to the equal access to medical care in Canada's universal health care system. Niu et al. found that uninsured and Medicaid insured patients with breast, cervical, colorectal, head and neck, lung, prostate or uterine cancer have higher mortality rates compared to patients with private insurance or Medicare. As substantial proportions of the US population are uninsured or enrolled in Medicaid, we examined the association between in-hospital mortality and different primary payers in patients with breast cancer.

Methods

Adult female admissions (adm) with a primary diagnosis of breast cancer between 1999 and 2014 were extracted from the National Inpatient Sample database using the ICD-9 code 174.9 (N=98631, for a weighted N=484859). The sample was weighted to approximate the full inpatient population of the US over the time period. To minimize the effect of changes in mortality rates based on insurance status over the time interval studied, we grouped the adm into three categories: Group 1 for adm from 1999 to 2003, Group 2 2004 to 2008, and Group 3 2009 to 2014. Chi-Square analysis was done to determine the in-hospital mortality rates by payer group and Cox Proportional Hazard regression was used to determine the hazard of death (HR) within 30 days of adm by payer.

Results

In-hospital Mortality (%) by primary payerYear GroupMedicareMedicaidPrivate InsuranceSelfpay/UninsuredP value13.836.773.4310.140.000124.587.554.9590.000132.843.463.0210.260.0001

Hazard ratio of death within the hospitalizationYear GroupMedicaid vs MedicareP valueUninsured vs MedicareP value12.03 (1.49, 2.76)0.00013.2 (2.49, 4.22)0.000121.56 (1.19, 2.46)0.00012.9 (2.20, 3.80)0.000132.55 (1.99, 3.27)0.00017.76 (1.99, 3.27)0.0001

The number of adm with Medicare or Private insurance were higher than those with Medicaid or Selfpay/uninsured. The in-hospital mortality was highest for Selfpay/uninsured, followed by admissions with Medicaid. After controlling for age, race, median income and comorbidities, the HR was significantly higher in the Medicaid and selfpay/uninsured admissions compared to Medicare admissions. In Group 1, compared to Medicare adm the HR was 103% higher for Medicaid and 220% higher for uninsured. In Group 2, the HR was 56% higher for Medicaid and 196% higher for uninsured. In Group 3, it was 155% higher for Medicaid and 676% higher in uninsured.

Conclusion

Even after controlling for other factors which are implicated in the mortality, the HR is significantly higher in Medicaid and uninsured admissions when compared with Medicare enrolled admissions with breast cancer. Equitable distribution of health was one of the “Aims for Improvement” in the Institute of Medicine's 2001 report, but our results suggests that this has not yet been achieved. Insurance status still appears to play a crucial role in patient outcomes and should be considered as a metric of equitable care. More scientific research is needed in the area of differential receipt of standard therapy in cancer patients considering the limitations of our study.

Citation Format: Perimbeti S, Chakunta H, Liu L, Ward K, Jain M, Styler M. Disparities in the risk of mortality in breast cancer based on health insurance status [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-10-21.

A novel and less invasive technique to assess cytokine profile of vitreous in patients of diabetic macular oedema

PurposeA pilot study to validate the collection of vitreous reflux (VR) after intravitreal injection using Schirmers tear strips was carried out. We assessed its efficiency for proteomics studies by estimating the differential expression of 27 cytokines using multiplexed bead array in diabetic macular oedema and proliferative diabetic retinopathy. To set, validate and assess the efficacy of Schirmer tear strips for collecting VR in patients undergoing intravitreal injections for diabetic macular oedema (DME).Patients and methodsVR samples were collected from 11 eyes of DME patients after intravitreal injections using Schirmer tear strips. Undiluted vitrectomy samples were obtained from six eyes of non-diabetic patients with idiopathic macular hole and seven eyes of diabetic patients with high-risk proliferative diabetic retinopathy (Hr-PDR), which were also subsampled on the Schirmer tear strips. Tear sampling was done in a subset of the DME patients. Total protein concentration between VR and vitrectomy samples was compared. Levels of the set of 27 cytokines in Schirmer tear strips samples were measured. Inter-group comparison for cytokines was done using Mann-Whitney U-test.ResultsSimilar protein concentration in VR samples and vitrectomy samples (P<0.05) was obtained. Tear protein contamination was not detected in VR samples. In comparison with no-DR patients, 25 and 20 of the measured 27 cytokines were significantly elevated (P<0.05) in the Hr-PDR and DME patients, respectively. As compared with no-DR patients, vascular endothelial growth factor was only moderately elevated in DME patients (P>0.05), but significantly elevated in Hr-PDR patients (P<0.05). Interleukin 1 receptor antagonist/interleukin 1b (IL1RA/IL1b) ratio was 13 times higher in DME patients as compared with Hr-PDR group.ConclusionWe demonstrated a simple, safe method of VR sampling. This technique provides a pure, albeit small, vitreous sample for proteomics. IL1RA/IL1b ratio was found to be 13-fold higher in the DME group as compared to the Hr-PDR.

Mucormycosis of the Thyroid Gland: A Cataclysmic Event in Renal Allograft Recipient

Invasive fungal infection is a complication seen in immunocompromised patients. A disseminated fungal infection has a high rate of mortality. Although disseminated infection is known to be seen in most organs, thyroid involvement is rarely reported. Hence, we report a fatal case of thyroid mucormycosis which resulted into laryngeal nerve paralysis and death of a renal allograft recipient.