Establishment of synchronization in carrot cell suspension culture and studies on stage specific activation of glyoxalase I

The present report summarizes and compares the effects of three cell cycle inhibitors, viz. aphidicolin, hydroxyurea and mimosine, in inducing synchronization of a rapidly proliferating suspension culture of carrot. These treatments efficiently synchronized the cell cycle as the doubling time of the cell population was roughly equal to the total length of one cell cycle. Protoplasts derived from mimosine treated cell suspension culture were resolved via flow cytometry to get an idea of the temporal organization of the cell cycle events. The biochemical analysis showed a rise in stage specific activity of glyoxalase I, an auxin inducible marker enzyme activated at G₂-M. This activity peak could be shifted to an early phase of interphase in response to auxin treatment.     

Polarization memory rate as a metric to differentiate benign and malignant tissues

Non-invasive optical methods for cancer diagnostics, such as microscopy, spectroscopy, and polarimetry, are rapidly advancing. In this respect, finding new and powerful optical metrics is an indispensable task. Here we introduce polarization memory rate (PMR) as a sensitive metric for optical cancer diagnostics. PMR characterizes the preservation of circularly polarized light relative to linearly polarized light as light propagates in a medium. We hypothesize that because of well-known indicators associated with the morphological changes of cancer cells, like an enlarged nucleus size and higher chromatin density, PMR should be greater for cancerous than for the non-cancerous tissues. A thorough literature review reveals how this difference arises from the anomalous depolarization behaviour of many biological tissues. In physical terms, though most biological tissue primarily exhibits Mie scattering, it typically exhibits Rayleigh depolarization. However, in cancerous tissue the Mie depolarization regime becomes more prominent than Rayleigh. Experimental evidence of this metric is found in a preliminary clinical study using a novel Stokes polarimetry probe. We conducted in vivo measurements of 20 benign, 28 malignant and 59 normal skin sites with a 660 nm laser diode. The median PMR values for cancer vs non-cancer are significantly higher for cancer which supports our hypothesis. The reported fundamental differences in depolarization may persist for other types of cancer and create a conceptual basis for further developments in polarimetry applications for cancer detection.     

Management and surgical outcomes of pediatric retinal detachment associated with familial exudative vitreoretinopathy – Our experience at a tertiary care ophthalmic center in North India

Purpose:To report the clinical profile, management, and long-term anatomical and visual acuity (VA) outcomes of pediatric macula-off rhegmatogenous retinal detachment (RRD) secondary to familial exudative vitreoretinopathy (FEVR).Methods: This was a prospective, interventional study of 14 eyes of 13 children aged ≤18 years with macula-off FEVR-RRD. The primary outcomes were anatomical reattachment and VA changes.Results: The mean (±SD) age of the study population was 12.14 (±3.23) years (range 6–18 years) with a male preponderance (M:F – 10:3). Of the 14 eyes, 10 underwent vitrectomy with silicone oil injection, while four underwent scleral buckling surgery. Significant improvement in VA was noted at a mean (±SD) follow-up duration of 3.32 (±1.34) years, with the mean (±SD) LogMAR VA improving from 1.42 (±0.48) (Snellen equivalent 2/60; range from 6/36 to counting finger close to face [CFCF]) to 0.6 (±0.31) (Snellen equivalent 6/24; range 6/9–6/36) (P < 0.00001) at the final visit. Successful anatomical reattachment was achieved in 13/14 eyes (92.85%). Screening of the other eye and family members was performed for FEVR and treated with laser photocoagulation when deemed necessary (7/10 contralateral eye; 12/20 siblings; 0/24 parents).Conclusion: To conclude, RRD may arise in eyes with FEVR at a young age and with a male predilection in Indian population. Timely surgical intervention by scleral buckling procedure or vitrectomy, based on the patient profile, can achieve excellent anatomical and VA outcomes. Careful clinical and angiographic screening of the other eye and family members is vital.     

Preservation of myocardial microcirculation during mechanical reperfusion for myocardial ischemia with either abciximab or eptifibatide

Myocardial Blush Grade (MBG) is an angiographic method of assessing myocardial microcirculation and provides independent risk stratification among patients with normal TIMI 3 flow. Although the beneficial effect of abciximab on microvascular perfusion is well established, the efficacy of eptifibatide in the prevention of platelet aggregation and distal microembolization is less proven. After a pharmacologic shift by our institution towards the use of eptifibatide in patients with unstable angina presenting for PCI, we sought to evaluate our experience by retrospectively comparing the effect on myocardial perfusion between abciximab and eptifibatide following PCI in stable angina or acute coronary syndrome. Microcirculatory perfusion was reviewed in 101 consecutive patients (23 stable angina, 61 unstable angina, 17 non-q MI) undergoing PTCA/stenting. This comparison was between the last group of 51 patients who routinely received standard bolus and infusion of abciximab and the first group of 50 patients who began receiving standard bolus and infusion of eptifibatide. Baseline characteristics between the two groups were balanced, except for more patients with previous CABG in the eptifibatide group. Angiograms were evaluated by 2 blinded independent reviewers for MBG as follows: 0, no blush; 1, minimal blush; 2, moderate blush; and 3, normal blush. TIMI 3 flow was seen in 98 patients. MBG scores were not significantly different in the abciximab group (67% MBG 3; 31% MBG 2; 2.0% MBG 0 1) than in the eptifibatide group (58% MBG 3; 36% MBG 2; 6.0% MBG 0 1); p = 0.34. Patients with prior PTCA/stenting had lower MBG scores (0 2) compared to patients without prior PTCA (58% vs 31%; p = 0.03). There were significantly lower MBG scores in all patients with prior PTCA or CABG compared to patients without (55% vs 30%; p = 0.03). MBG scores significantly and inversely correlated with peak troponin I levels (r = -0.18, one-tailed p = 0.04). The similarity in myocardial perfusion between abciximab and eptifibatide suggests that both compounds are equally effective in reducing platelet aggregation and microembolization during mechanical reperfusion. Lower MBG scores in patients with prior PTCA or revascularization may be explained by irreversible microvascular dysfunction resulting from distal microembolization during the previous procedure. Lower MBG scores in patients with higher troponin I levels may reflect more frequent microemboli and microinfarcts during an ischemic event. Larger prospective studies need to be performed to validate these findings.     

Efficacy of urinary N-acetyl-β-D-glucosaminidase to evaluate early renal tubular damage as a consequence of type 2 diabetes mellitus: a cross-sectional study

We assessed the prognostic accuracy of urinary N-acetyl-β-D-glucosaminidase (NAG), an early proximal tubular damage marker for the onset of diabetic nephropathy. The study included 491 eligible participants with 76 healthy controls, 194 type 2 diabetes mellitus (T2DM) patients with 0–5, 5–10, 10–15, and 15–20 years of T2DM duration, 71 microalbuminuric patients, 100 diabetic nephropathy patients, and 50 non-diabetic nephropathy patients. Fasting glucose, serum fructosamine, HbA1C, urinary microalbumin, serum creatinine, estimated glomerular filtration rate (eGFR), serum NAG, and urinary NAG were estimated. We compared urinary NAG activity with other well-established markers of diabetic nephropathy like microalbuminuria, eGFR, and serum creatinine. Urinary NAG excretion was increased by 8 and 12 folds in T2DM patients of 10–15 and 15–20 years of diabetes duration (p < 0.0001), respectively, without the appearance of microalbuminuria. The urinary NAG activity increased 16 and 18 fold in moderately increased albuminuria and diabetic nephropathy patients, respectively (p < 0.0001), without any change in non-diabetic nephropathy patients. A cutoff value of 3 U/L of urinary NAG has demonstrated a sensitivity of 96.1 % and a specificity of 100 % discriminating healthy controls from patients with T2DM duration of 10–15 years (AUC 1.000) and 15–20 years (AUC 0.999); microalbuminuria (AUC 0.999), and diabetic nephropathy (AUC 1.000). Urinary NAG excretion gradually increases with the increase in duration of diabetes and appeared much before the microalbuminuria, decreased eGFR, and increased serum creatinine. Thus, the urinary NAG may be considered as a potential site-specific early tubular damage marker leading to diabetic nephropathy.

     

Toxigenic Helicobacter pylori induces changes in the gastric mucosal microcirculation in rats

BACKGROUND AND AIMS: One of the key components of inflammation is changes in vascular structure and function. This suggests that the microcirculation may be a key target of Helicobacter pylori released factors. It has previously been shown in vivo that pooled H pylori extracts from duodenal ulcer/gastritis patients induce platelet aggregation but no leucocyte activation within rat gastric mucosal microcirculation (GMMC). However, infection with strains associated with ulcer disease as compared with gastritis may exert greater effects on the microcirculation. This study used fluorescent in vivo microscopy to determine the acute effects of extracts of genotypically different H pylori strains on the GMMC. METHODS: Three H pylori extracts, with different cagA and VacA toxigenic status, were individually administered to the gastric mucosa of anaesthetised Wistar rats. The mucosal surface was visualised via an incision made in the exteriorised stomach. Fluoroscein isothiocyanate conjugated to bovine serum albumin (FITC-BSA) or acridine orange was used to quantify macromolecular leak (MML) and leucocyte/platelet activity respectively for 120 minutes. Changes in capillary and post-capillary venule (PCV) diameters were also monitored. RESULTS: The cagA(+) VacA toxigenic strain 60190 induced significant and sustained MML by five minutes (p<0.01). Transient and less leakage was observed with its isogenic VacA(-) mutant and other non-toxigenic strains regardless of cagA status. Significant increases in leucocyte adhesion (p<0.05), platelet aggregation (p<0.05), and PCV vasoconstriction (p<0.05) were only observed with the cag A(+) and toxigenic strain. CONCLUSION: Extracts of H pylori are capable of inducing marked disturbances within the rat GMMC. These disturbances seem to be dependent on the production of an active vacuolating cytotoxin. Varying effects on the GMMC may explain the clinically diverse outcomes associated with genotypically different strains.     

Mechanisms of Helicobacter pylori-Induced Rat Gastric Mucosal Microcirculatory Disturbances In Vivo

The exact mechanisms by which Helicobacter pylori infection results in gastric mucosal injury are unclear. However, it has been demonstrated that surface protein extracts of the bacterium can induce a number of disturbances within the rat gastric mucosal microcirculation, including platelet aggregation and macromolecular leakage (MML) of labeled albumin. This study aimed to determine the mechanisms involved in inducing these events using the technique of fluorescent in vivo microscopy. Male Wistar rats were pretreated with either ketotifen, a mast cell stabilizer (1 mg/kg), pyrilamine, an H₁-receptor antagonist (30 mg/kg), hexanolamine-PAF, a PAF-receptor antagonist (10 g/kg), l-arginine, the nitric oxide precursor (300 mg/kg) or vehicle, saline. Then 0.5 ml of H. pylori extract was administered to the exteriorized gastric mucosa of the anesthetized rat. Alterations in fluorescein-labeled albumin leak, vessel diameters, and acridine red-labeled leukocyte and platelet activity were determined over a 2-hr period. Saline pretreated animals demonstrated significant MML with a peak at 5 min (11%, P < 0.02). This was prevented with ketotifen and pyrilamine, but not with hexanolamine-PAF (17.5%, P < 0.05) and l-arginine (13%, P < 0.05). Significant numbers of platelet emboli and thrombi were observed within mucosal capillaries and postcapillary venules with vehicle pretreatment; this was prevented with hexanolamine-PAF and l-arginine, but not with ketotifen and pyrilamine. In conclusion, these studies demonstrate that more than one mediator is involved in inducing the rat gastric mucosal microcirculatory disturbances associated with H. pylori administration. Mast cells and histamine are linked to MML, with PAF, probably not derived from mast cells, involved in platelet activation.     

Pituitary Apoplexy in a Patient with Acute Myeloid Leukemia and Thrombocytopenia

We describe a 72-year-old woman with a history of acute myeloid leukemia who developed pituitary apoplexy associated with thrombocytopenia secondary to chemotherapy. She presented with new onset severe headache, nausea, vomiting and blurred vision. Initial physical examination was unremarkable. CT scan of the head was initially negative. Upon admission for further work up, She developed a high-grade fever, hypotension and obtundation. Subsequent physical examination revealed bitemporal visual fields defects and decreased visual acuity. Repeat imaging of head revealed a hemorrhagic pituitary mass compressing the optic chiasm. Laboratory results were compatible with the diagnosis of pan-hypopituitary syndrome. She received high dose steroids and was transferred for transnasal sphenoidotomy decompression surgery. The visual defects improved postoperatively. A literature review of Pituitary apoplexy is presented. Pituitary apoplexy secondary to thrombocytopenia has never been reported.     

Heterosis and Combining Ability for Mineral Nutrients in Snowball Cauliflower (<Emphasis Type="Italic">Brassica oleracea</Emphasis> var. <Emphasis Type="Italic">botrytis</Emphasis> L.) Using <Emphasis Type="Italic">Ogura</Emphasis> Cytoplasmic Male Sterile Lines

Development of nutritionally rich hybrids is one of the main breeding objectives in vegetable crops to counter micronutrient malnutrition. The present study evaluates the combining ability and heterosis for different dietary minerals in snowball cauliflower. Five genetically diverse Ogura cytoplasmic male sterile (CMS) lines of cauliflower and seven male fertile testers were crossed in line × tester mating scheme to obtain 35 F₁ hybrids. The assessment of the F₁s along with their parental lines for 8 important macro- and microelements revealed a wide range of heterosis. The CMS line, Ogu 13-85 was identified as a good general combiner for sodium (Na), calcium (Ca), iron (Fe), zinc (Zn) and manganese (Mn) content, whereas Ogu 101 for Mn, Zn, sulphur (S) and magnesium (Mg) contents. The lines with better general combining ability (GCA) produced majority of the heterotic hybrids. However, GCA alone was not sufficient to determine and identify the potential parental lines. The hybrid, Ogu 101 × Lalchowk Maghi was found to be the best heterotic combination for potassium (K), S and Zn content. The cross Ogu 13-85 × Lalchowk Maghi was the best heterotic hybrid for Na and Ca content. The cross-combinations Ogu 13-85 × DB-187, Ogu 13-01 × DB-187 and Ogu 13-01 × Sel-26 showed high heterosis for accumulation of Mg, Fe and Mn, respectively. It was observed that both GCA and specific combining ability were important for heterosis of mineral content in snowball cauliflower.