Consequence of cyclic pollen selection for heat tolerance on the performance of different generations in maize (Zea mays L.).

The reproductive stage in many crops, including maize, is very sensitive to heat stress and the genetic overlap between gametophytic and sporophytic phase gives an opportunity to select superior stress tolerant genotype at gametophytic stage. An attempt was made to evaluate the response of cyclic pollen selection in the F1 and F2 generations on the performance of F3 generation progenies for seed yield and yield contributing traits under natural heat stress conditions. In this direction three groups of F3 progenies, namely (i) pollen selection in F1 and F2 generations (GG), (ii) pollen selection only in F2 generation (CG), (iii) no pollen selection in F1 and F2 generations (CC) were screened for heat stress at Agricultural Research Station (ARS), Bheemarayanagudi. The GG progenies recorded significantly higher chlorophyll content, more number of pollen grains per anther and less pollen sterility compared to CG and CC group of progenies under heat stress. Further, the F4 progenies obtained through cyclic pollen selection (in F1, F2 and F3) were also tested for heat stress tolerance at seedling stage. The significant improvement for heat stress tolerance was recorded in F4 progenies derived through cyclic pollen selection as compared to control (no pollen selection for heat tolerance in any generation) F4 progenies. The results indicated that cyclic pollen selection in F1, F2 and F3 generations improved the heat stress tolerance of the progenies in the succeeding generations. To provide genetic evidence for the effect of pollen selection for heat tolerance, the control F2 (C) and selected F2 (G) populations were compared for the segregation of SSR markers. The selected F2 (G) population showed significant deviation from normal Mendelian ratio of 1:2:1 and showed skewness towards the alleles selected from male parent. The results provide strong evidence for an increase in the frequency of parental alleles in the progenies that impart heat stress tolerance.

Effect of footplate neuromuscular electrical stimulation on functional and quality-of-life parameters in patients with peripheral artery disease: pilot, and subsequent randomized clinical trial.

BACKGROUND: Supervised exercise programmes for intermittent claudication have poor access and limited compliance. Neuromuscular electrical stimulation (NMES) may be an effective alternative. A proof-of-concept study and RCT were conducted. METHODS: In study 1, eligible patients underwent baseline assessment; treadmill testing for initial (ICD) and maximum (MCD) claudication distance; EuroQoL Five Dimensions five-level instrument (EQ-5D-5L™) and Intermittent Claudication Questionnaire (ICQ) assessment; and measurement of ultrasound haemodynamics of the superficial femoral artery. After familiarization with the NMES device, participants underwent a 30-min session of stimulation with concomitant recording of haemodynamic measures at 15 min, and after device cessation. Measurements were repeated after 6 weeks of daily use of NMES. In study 2, consecutive patients underwent baseline assessment before online randomization to a supervised exercise programme only, or adjunctive NMES treatment for 6 weeks, followed by repeat measurements. RESULTS: Study 1 (20 patients) showed a significant improvement in MCD (46 per cent; P < 0·001) and ICD (71 per cent; P < 0·001). The RCT (42 patients) showed a significant adjunctive benefit of NMES in ICD (46 per cent; P = 0·014). Improvements were seen in the ICQ (9 points; P = 0·009) and EQ-5D-5L™ (P = 0·007) in study 1, and there was a significant adjunctive benefit of NMES on the ICQ score in patients who did supervised exercise (11·2 points; P = 0·031). Blood volume flow and time-adjusted mean velocity increased significantly with the device on (P < 0·050). Overall, NMES compliance exceeded 95 per cent. CONCLUSION: Footplate NMES significantly improved walking distance in patients with intermittent claudication when used independently and also as an adjunct to supervised exercise. Registration number: trial 1, NCT02436200; trial 2, NCT02429310 (http://www.clinicaltrials.gov).

ANTECEDENTES: Los programas de ejercicio supervisado (supervised exercise programmes, SEP) para la claudicación intermitente (intermittent claudication, IC) tienen un acceso y un cumplimiento deficientes. La estimulación eléctrica neuromuscular (neuromuscular electrical stimulation, NMES) puede ser una alternativa clínicamente efectiva. Se realizó un estudio de prueba de concepto y un ensayo controlado aleatorizado. MÉTODOS: Estudio 1: Veinte pacientes elegibles se sometieron a una evaluación inicial que incluía una prueba en la cinta de correr para la distancia inicial de claudicación (initial claudication distance, ICD) y la distancia máxima de claudicación (maximum claudication distance, MCD), EuroQoL-5D (EQ-5D), valoración mediante el cuestionario de claudicación intermitente (intermittent claudication questionnaire, ICQ), y hemodinámica por ecografía de la arteria femoral superficial. Después de familiarizarse con el dispositivo NMES, los participantes se sometieron a una sesión de estimulación de 30 minutos con el registro concomitante de medidas hemodinámicas a los 15 minutos y después del cese del dispositivo. Se realizaron mediciones repetidas después de 6 semanas de uso diario de NMES. Estudio 2: Se reclutaron 42 pacientes que tras una evaluación inicial y posterior aleatorización al azar en línea, se asignaron al Grupo A, utilizando SEP solamente; o al el Grupo B, con tratamiento NMES complementario durante 6 semanas seguido de medidas repetidas. RESULTADOS: El estudio 1 mostró una mejoría significativa de la MCD (46%, P < 0,0001) y de la ICD (71%, P < 0.004). El ensayo clínico mostró un beneficio coadyuvante significativo de NMES en la ICD (46%, P = 0,014). Se observaron mejorías en la puntuación del ICQ (9 puntos, P < 0,01) y del EQ-5D (P < 0,05) en el estudio 1, con un beneficio coadyuvante significativo de NMES en la puntuación del ICQ (11 puntos, P < 0,05). El flujo de volumen de sangre (CC/min) y TAMV (cm/s) aumentaron significativamente con el dispositivo en funcionamiento (P < 0,05). El cumplimiento global de la NMES superó el 95%. CONCLUSIÓN: La plataforma de NMES para el pie mejora significativamente las distancias de caminar en la claudicación intermitente cuando se usa de forma independiente y también proporciona un beneficio complementario al ejercicio supervisado en la distancia caminada sin dolor. La mejora del flujo sanguíneo puede ser un mecanismo para explicar estos resultados.

Non-Invasive Management of Peripheral Arterial Disease.

BACKGROUND: Peripheral arterial disease (PAD) is common and symptoms can be debilitating and lethal. Risk management, exercise, radiological and surgical intervention are all valuable therapies, but morbidity and mortality rates from this disease are increasing. Circulatory enhancement can be achieved using simple medical electronic devices, with claims of minimal adverse side effects. The evidence for these is variable, prompting a review of the available literature. METHODS: Embase and Medline were interrogated for full text articles in humans and written in English. Any external medical devices used in the management of peripheral arterial disease were included if they had objective outcome data. RESULTS: Thirty-one papers met inclusion criteria, but protocols were heterogenous. The medical devices reported were intermittent pneumatic compression (IPC), electronic nerve (NMES) or muscle stimulators (EMS), and galvanic electrical dressings. In patients with intermittent claudication, IPC devices increase popliteal artery velocity (49-70 %) and flow (49-84 %). Gastrocnemius EMS increased superficial femoral artery flow by 140 %. Over 4.5-6 months IPC increased intermittent claudication distance (ICD) (97-150 %) and absolute walking distance (AWD) (84-112 %), with an associated increase in quality of life. NMES of the calf increased ICD and AWD by 82 % and 61-150 % at 4 weeks, and 26 % and 34 % at 8 weeks. In patients with critical limb ischaemia IPC reduced rest pain in 40-100 % and was associated with ulcer healing rates of 26 %. IPC had an early limb salvage rate of 58-83 % at 1-3 months, and 58-94 % at 1.5-3.5 years. No studies have reported the use of EMS or NMES in the management of CLI. CONCLUSION: There is evidence to support the use of IPC in the management of claudication and CLI. There is a building body of literature to support the use of electrical stimulators in PAD, but this is low level to date. Devices may be of special benefit to those with limited exercise capacity, and in non-reconstructable critical limb ischaemia. Galvanic stimulation is not recommended.

Randomised Controlled Trial: Potential Benefit of a Footplate Neuromuscular Electrical Stimulation Device in Patients with Chronic Venous Disease.

OBJECTIVES: Chronic venous disease (CVD) is common, affecting a quarter of the population. Current conservative methods of treatment aim to prevent progression of disease by reducing ambulatory venous pressure. Neuromuscular electrical stimulation (NMES) refers to the use of electrical impulses to elicit muscle contraction. This pilot randomised controlled trial investigates the effect of a footplate NMES device (REVITIVE) on venous flow parameters, limb oedema, and quality of life outcome measures in patients with CVD. METHODS: Twenty-two patients with Clinical Etiological Anatomical and Pathophysiological (CEAP) clinical class C2-C4 venous disease were randomised to receive a sham or test device. The recommended duration of use was for 30 minutes daily for 6 weeks. Venous flow parameters (duplex ultrasound), limb volume (optoelectric volumeter), and quality of life outcome measures were measured at baseline and after 6 weeks. RESULTS: The mean age of participants was 62 years, body mass index 28.6, with a 15:7 female preponderance. There was a significant difference in the percentage change in femoral vein flow parameters (from baseline) between the test and sham group while using the device (Week 0 time-averaged mean velocity 102.4% vs. -9.1%, p < .0001; volume flow 107.9% vs. -3.7%, p < .0001; peak velocity 377.7% vs. -6.7%, p < .0001). Limb volume was observed to increase significantly in the sham group (2.0% at Week 0 and 1.2% at Week 6; p < .01). This was prevented in the test group (+0.8% at Week 0 and 1.0% at Week 6; p = .06). There was a significant difference in the Aberdeen Varicose Vein Questionnaire between the two groups over the 6 weeks. CONCLUSIONS: This trial demonstrated a significant difference in venous flow parameters and prevention of orthostatic limb oedema with NMES. There was a positive effect on quality of life. Larger studies are required to determine the clinical significance of this in patients with venous disease.

Development and evaluation of in situ novel intragastric controlled-release formulation of hydrochlorothiazide.

In situ forming intragastric controlled-release formulation is a new technology in the field of oral controlled-release delivery systems. The objective of this study was to develop formulations that can control drug release up to 24 hours. In addition, a combination of appropriate polymers and solvents was selected that could form a drug loaded gel at the process temperature of 60-70 °C, which gel could turn into a rigid mass upon exposure to dissolution fluid at body temperature. The drug release mechanism from this rigid mass was controlled by different formulation factors such as different polymer grades, polymer concentrations, hydrophobicity or hydrophilicity of solvents, different drug loadings, and physicochemical properties of additional excipients. After evaluating different formulation factors, Ethocel 10 FP and triethyl citrate were selected for further studies using hydrochlorothiazide as a model drug. Polynomial correlation between viscosity of the blank gel and drug release profile was also obtained.

Genetic evidence for gametophytic selection of wilt resistant alleles in chickpea.

Gametophytic selection can drastically reduce the number of selection cycles during crop improvement programs. The objective of the present investigation was to test whether the nature of inheritance of two unlinked disease-resistant loci, h(1) and h(2), against Fusarium wilt in chickpea (Cicer arietinum L.) under gametophytic (pollen) selection was similar to that already observed at sporophytic level. A homozygous dominant (H(1)H(1)H(2)H(2)) susceptible genotype JG-62 was crossed to a recessive (h(1)h(1)h(2)h(2)) resistant genotype WR-315 to produce 20 F(1) hybrid seeds. In the following generation, flower buds of 10 F(1) hybrid plants were subjected to toxin stress before anthesis and the remaining ten control F(1) plants' flowers were sprayed with water. Thirty-four selected BC(1) plants were generated by test crossing resistant WR-315 individuals with pollen from toxin-stressed F(1) individuals. Both control and treated F(1) plants were selfed to produce respective F(2) generations. Two DNA markers, CS-27(700bp) and A07C(430bp), linked to susceptible alleles H(1) and H(2), respectively, were used to study the inheritance patterns of h(1) and h(2) loci in the F(2) and BC(1) generations. One hundred and forty-four selected F(2), 129 control F(2), and 34 selected backcross individuals were tested for the presence or absence of DNA markers. Except for the control F(2), observed ratios of selected F(2) and BC(1) populations exhibited significant chi-square deviations from expected monogenic and digenic ratios. Our results suggest that gametophytic selection is as effective as that realized at the sporophytic level, and that the gametophytic selection can be an effective breeding tool for plant breeding programs.