In-vitro Wound Healing Assays: A Comprehensive Review

Chronic non-healing wounds offer a tough clinical challenge for plastic and reconstructive surgeons. A systematic comprehension of the underlying mechanism of wound healing is essential for improved patient care. It is also required to know the complex and continuing armamentarium of therapeutic choices for treatment of chronic wounds. Wound assays are excellent way to apprehend the wound healing progression and the efficacy of various products that contribute and promote in wound healing. In the production sequence of wound care products also, human trials are often preceded by more economical in-vitro or preclinical studies. Wound healing assays are to understand the principal molecular mechanisms involved in repair progression and used in the exploration of impending therapeutics and designing treatment protocols intended for better curing. Several prototypes of wound healing have been established and are well-accepted. This review focuses on in vitro assays, as they are pre-requisite preliminary assays that are rapid, economical and ethical substitute to other complex assay models. Literature exploration for data sources were carried out through a meticulous search in indexed literature and various website centered educational research documents. In total 76 studies were earmarked from 286 most relevant scholarly articles. An extensive criterion to describe both in-vitro assays and in-vitro assays in wound healing has been used for probing the comments. Also, personal resources have been used for information gathering. The present manuscript provides a broad overview of various in-vitro assays with descriptive account of injury techniques with assessment of pros and cons of each. It also emphasized on three-dimensional culture assays, which utilizes bioengineered prototypes to exhibit various connections and the mechanisms of diverse sort of cells in the wound healing.

Abstract PD13-05: PD13-05 Updated results of a Phase 1b study of gedatolisib plus palbociclib and endocrine therapy in women with hormone receptor positive advanced breast cancer: Subgroup analysis by PIK3CA mutation status

Background: Addition of PI3K/mTOR inhibitor after progression on CDK4/6 inhibitor (CDK4/6i) and endocrine therapy (ET) can potentially restore sensitivity to CDK4/6i and prevent adaptive activation of the PI3K/mTOR pathway. To evaluate this hypothesis, we conducted a Phase Ib study of gedatolisib (G), a dual inhibitor of PI3K/mTOR, palbociclib (P) a CDK4/6i, and ET (with letrozole [LET] or fulvestrant [FUL]) in women with hormone receptor positive (HR+)/HER2- advanced breast cancer (ABC). Manageable toxicity and preliminary antitumor activity were observed in 35 patients(pts) enrolled in the dose escalation portion of the study (Forero-Torres, ASCO 2018) and 103 pts enrolled in the expansion portion of the study (Layman, SABCS 2021). Here, we report updated efficacy and safety data and sub-group analysis by PIK3CA mutation status in the four expansion study arms with a March 3, 2022, data cut-off.

Methods: Pts with HR+/HER2- ABC were treated in four expansion arms: A) G+P+LET as first-line treatment, B) G+P+FUL as 2nd line treatment in pts without prior CDK4/6i; C & D) G+P+FUL as 2nd or 3rd line therapy in pts with prior CDK4/6i. P, LET, and FUL were administered at standard doses. G 180 mg was intravenously administered weekly in Arms A, B, and C and three weeks on/one week off in Arm D. The primary endpoint was investigator assessed objective response rate (ORR). Secondary endpoints included safety, duration of response and progression free survival (PFS).

Results: Of the 103 pts treated with G+P+ ET in the expansion arms (A-D), 100% had measurable disease at baseline, 71% (73/103) lacked PIK3CA mutations (wild type; WT), 27% (28/103) had PIK3CA-mutations (MT), 70% (72/103) had evidence of bone metastases, and 59% (61/103) had liver metastases. The most frequent grade 3 and 4 treatment related AEs (TRAE) with G+P+ET included neutropenia (63%), stomatitis (27%), rash (20%), fatigue (11%) and hyperglycemia (7%). Treatment discontinuation due to TRAEs was 6.5% in Arm A, 15.4% in Arm B, 9.4% in Arm C and 3.7% in Arm D. Efficacy data for each arm is presented in Table 1. Promising ORR and PFS were seen in all arms regardless of PIK3CA mutation status. In Arm D, ORR was 63% overall, 73% in PIK3CA-MT pts, and 60% in PIK3CA-WT pts. Median PFS in Arm D was 12.9 months with a median follow up of 29 months. 60% and 48% of pts in the PIK3CA-MT and PIK3CA-WT Arm D sub-groups, respectively, were progression free at 12 months.

Conclusions: These preliminary data demonstrate promising activity of G+P+ET combination in pts who were CDK4/6i-naïve and in those whose disease progressed on or after CDK4/6i therapy regardless of PIK3CA mutation status. Encouraging results in CDK4/6i treatment naïve patients warrant further evaluation of gedatolisib in combination with CDK4/6i treatment in the front-line setting. Arm D results provide a strong basis for the initiated Phase 3 study (VIKTORIA-1) in pts whose disease progressed on or after CDK4/6i therapy.

Table 1. Efficacy Data by Expansion Arms

Citation Format: Robert Wesolowski, Hope Rugo, Erica Stringer-Reasor, Hyo S. Han, Jennifer M. Specht, E. Claire Dees, Peter Kabos, Ulka Vaishampayan, Seth A. Wander, Janice Lu, Keerthi Gogineni, Alexander I. Spira, Anne F. Schott, Maysa Abu-Khalaf, Pratima Nayak, Brian F. Sullivan, Igor Gorbatchevsky, AND Rachel M. Layman. PD13-05 Updated results of a Phase 1b study of gedatolisib plus palbociclib and endocrine therapy in women with hormone receptor positive advanced breast cancer: Subgroup analysis by PIK3CA mutation status [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD13-05.

Pituitary Stalk Stretch Predicts Postoperative Diabetes Insipidus After Pituitary Macroadenoma Transsphenoidal Resection

BACKGROUND

Manipulation of the pituitary stalk, posterior pituitary gland, and hypothalamus during transsphenoidal pituitary adenoma resection can cause disruption of water electrolyte regulation leading to diabetes insipidus (DI).

OBJECTIVE

To determine whether pituitary stalk stretch is an independent risk factor for postoperative DI after pituitary adenoma resection.

METHODS

A retrospective review was performed of patients undergoing endoscopic endonasal resection of pituitary macroadenoma between July 2010 and December 2016 by a single neurosurgeon. We analyzed preoperative and postoperative imaging metrics to assess predictors for postoperative DI.

RESULTS

Of the 234 patients undergoing resection, 41 (17.5%) developed postoperative DI. DI was permanent in 10 (4.3%) and transient in 31 (13.2%). The pituitary stalk stretch, measured as the change in stalk length from preoperative to postoperative imaging, was greater in the DI compared with the non-DI group (10.1 mm vs 5.9 mm, P < .0001). The pituitary stalk stretch was associated with DI with significant difference in mean pituitary stalk stretch between non-DI group vs DI group (5.9 mm vs 10.1 mm, P < .0001). Multivariate analysis revealed that pituitary stalk stretch >10 mm was a significant independent predictor of postoperative DI [odds ratios = 2.56 (1.10-5.96), P = .029]. When stratified into transient and permanent DI, multivariable analysis showed that pituitary stalk stretch >10 mm was a significant independent predictor of transient DI [odds ratios = 2.71 (1.0-7.1), P = .046] but not permanent DI.

CONCLUSION

Postoperative pituitary stalk stretch after transsphenoidal pituitary adenoma surgery is an important factor for postoperative DI. We propose a reconstruction strategy to mitigate stalk stretch.

Temporal mechanisms of myogenic specification in human induced pluripotent stem cells

Understanding the mechanisms of myogenesis in human induced pluripotent stem cells (hiPSCs) is a prerequisite to achieving patient-specific therapy for diseases of skeletal muscle. hiPSCs of different origin show distinctive kinetics and ability to differentiate into myocytes. To address the unique cellular and temporal context of hiPSC differentiation, we perform a longitudinal comparison of the transcriptomic profiles of three hiPSC lines that display differential myogenic specification, one robust and two blunted. We detail temporal differences in mechanisms that lead to robust myogenic specification. We show gene expression signatures of putative cell subpopulations and extracellular matrix components that may support myogenesis. Furthermore, we show that targeted knockdown of ZIC3 at the outset of differentiation leads to improved myogenic specification in blunted hiPSC lines. Our study suggests that β-catenin transcriptional cofactors mediate cross-talk between multiple cellular processes and exogenous cues to facilitate specification of hiPSCs to mesoderm lineage, leading to robust myogenesis.

Fostamatinib disodium hexahydrate: a novel treatment for adult immune thrombocytopenia

Immune thrombocytopenia (ITP) is an autoimmune disease associated with substantial heterogeneity and varying outcomes. Significant bleeding, including intracranial hemorrhage, is a persistent risk for patients with ITP, along with cardiovascular disease. ITP has also been associated with decreased patient functionality and quality of life. The primary goal of ITP therapy is to lower the risk of bleeding and associated complications by raising platelet counts to levels that provide adequate hemostasis with minimal treatment-related toxicity. Current first-line treatments include corticosteroids, as well as intravenous and anti-D immunoglobulin. Despite the availability of several second-line options, the need for additional treatment options that can provide a stable, long-term response with few adverse effects is critical and ongoing. Fostamatinib disodium hexahydrate is an oral spleen tyrosine kinase inhibitor that produces a rapid, durable response in patients who have failed one or other treatments. Additionally, fostamatinib is well tolerated, and adverse effects can be actively mitigated through dose reduction, dose interruption, or standard therapeutic approaches.

Predictors of Postoperative Diabetes Insipidus Following Endoscopic Resection of Pituitary Adenomas

Context

The development of diabetes insipidus (DI) following transsphenoidal resection of pituitary adenomas has been associated with higher postsurgical morbidity and longer hospitalizations. Identifying these patients promptly and efficiently can lead to improved health care outcomes.

Objective

We evaluated our institution’s incidence of DI following pituitary adenoma resection and assessed for preoperative risk factors that were associated with postoperative DI.

Design

A retrospective review of 271 patients who underwent endoscopic endonasal resection of a pituitary adenoma between July 2010 and December 2016 by a single neurosurgical provider was completed.

Setting

All cases were from a single-center, academic institution.

Patients

Patients with a pituitary adenoma diagnosis confirmed on histology were included in the study. Those with previous surgery by a different provider were excluded.

Results

The incidence of DI at our institution was 16.6% (45 of 271 patients), with only 4% (11 patients) having permanent DI. The presence of visual abnormalities (CI 1.29 to 4.75), suprasellar extension (CI 1.36 to 6.88), and maximal tumor diameter (1.02 to 1.08) was significantly associated with an increased incidence of postoperative DI (P < 0.05). Hyperprolactinemia, tumor functionality, and cerebrospinal fluid exposure were not associated with higher rates of postoperative DI (P > 0.05).

Conclusion

Pituitary adenoma patients presenting with visual abnormalities, suprasellar extension, or large tumors are at higher risk of developing DI postoperatively. These patients warrant closer postoperative monitoring as well as adequate preoperative counseling to decrease their postsurgical morbidity.

Osteonecrosis of the Jaw among Patients Receiving Antiresorptive Medication: A 4-year Retrospective Study at a Tertiary Cancer Center, Kerala, India

Purpose:

Osteonecrosis of the jaw (ONJ) is a rare but complicated side effect of antiresorptive medications. The aim of the study is to evaluate the dental and drug-related factors related to ONJ among patients on these drugs at a tertiary cancer center, India.

Methodology:

A retrospective record review of patients who received antiresorptive medication at our center from 2011 to 2014 was done. The demographic factors, type, dosage, and duration of the medication and dental history were collected, and the data were entered an analyzed using Epidata software.

Results:

A higher incidence of ONJ (8.1%) was noted in our sample (n = 183). Dental intervention after zoledronic acid (ZA) administration showed a statistical significance (P < 0.001). No significance (P value) was noted with respect to sex (0.78), age (0.28), median duration (0.9), and median dosage (0.9) of ZA.

Conclusion:

Oro-dental screening and dental monitoring shall reduce the incidence of ONJ. Within the limitations of our study, no significant relation could be pointed toward the dosage and duration of the drug and development of ONJ.

SPINS-IND: Pellet injector for fuelling of magnetically confined fusion systems

Using a Gifford-McMahon cycle cryocooler based refrigeration system, a single barrel hydrogen pellet injection (SPINS-IND) system is indigenously developed at Institute for Plasma Research, India. The injector is based on a pipe gun concept, where a pellet formed in situ in the gun barrel is accelerated to high speed using high pressure light propellant gas. The pellet size is decided by considering the Greenwald density limit and its speed is decided by considering a neutral gas shielding model based scaling law. The pellet shape is cylindrical of dimension (1.6 mm ℓ × 1.8 mm φ). For pellet ejection and acceleration, a fast opening valve of short opening duration is installed at the breech of the barrel. A three-stage differential pumping system is used to restrict the flow of the propellant gas into the plasma vacuum vessel. Diagnostic systems such as light gate and fast imaging camera (240 000 frames/s) are employed to measure the pellet speed and size, respectively. A trigger circuit and a programmable logic controller based integrated control system developed on LabVIEW enables to control the pellet injector remotely. Using helium as a propellant gas, the pellet speed is varied in the range 650 m/s-800 m/s. The reliability of pellet formation and ejection is found to be more than 95%. This paper describes the details of SPINS-IND and its test results.

Flavored e-cigarette use: Characterizing youth, young adult, and adult users

The purpose of this study is to investigate how the use of flavored e-cigarettes varies between youth (12-17 years old), young adults (18-29 years old), and older adults (30 + years old). Cross-sectional surveys of school-going youth (n = 3907) and young adult college students (n = 5482) in Texas, and young adults and older adults (n = 6051) nationwide were administered in 2014-2015. Proportions and 95% confidence intervals were used to describe the percentage of e-cigarette use at initiation and in the past 30 days that was flavored, among current e-cigarette users. Chi-square tests were applied to examine differences by combustible tobacco product use and demographic factors. Most e-cigarette users said their first and "usual" e-cigarettes were flavored. At initiation, the majority of Texas school-going youth (98%), Texas young adult college students (95%), and young adults (71.2%) nationwide said their first e-cigarettes were flavored to taste like something other than tobacco, compared to 44.1% of older adults nationwide. Fruit and candy flavors predominated for all groups; and, for youth, flavors were an especially salient reason to use e-cigarettes. Among adults, the use of tobacco flavor at initiation was common among dual users (e-cigarettes + combustible tobacco), while other flavors were more common among former cigarette smokers (P = 0.03). Restricting the range of e-cigarette flavors (e.g., eliminating sweet flavors, like fruit and candy) may benefit youth and young adult prevention efforts. However, it is unclear what impact this change would have on adult smoking cessation.

Same-day light-emitting diode fluorescence microscopy for the diagnosis of tuberculosis in Chhattisgarh, India

SETTING

Three medical college hospitals using light-emitting diode fluorescence microscopy (LED-FM) for diagnosing tuberculosis (TB) in Chhattisgarh, India.

OBJECTIVES

To assess and compare the proportion of sputum smear-positive TB patients diagnosed through same-day microscopy (spot-spot) strategy or with the conventional (spot-morning) strategy.

METHODS

During November 2012 - March 2013, all consecutively enrolled presumptive TB patients (aged ≥ 18 years) were requested to provide three specimens: two spot specimens collected 1 h apart on the first day and one early morning specimen the next day; these were stained using auramine-O and examined using LED-FM.

RESULTS

Of 1716 (93% of total 1845) presumptive TB patients who provided all three specimens, 218 (13%) were smear-positive: 200 (11.7%) by same-day microscopy and 217 (12.7%) by the conventional method (McNemar's χ(2) 13.5, df 1, P = 0.0002). Eighteen (8.3%) cases were missed by the same-day method.

CONCLUSION

Although LED-FM is more sensitive to paucibacillary samples, 8% of smear-positive cases were missed using the same-day method. These findings indicate the need to revisit the global applicability of the current World Health Organization recommendation of switching to same-day diagnosis from the conventional policy.

Studies on growth morphology, UV absorbance and luminescence properties of sulphur doped ZnO nanopowders synthesized by the application of ultrasound with varying input power

Sulphur doped ZnO nanopowders have been prepared by sonochemical method in continuous (CS) and pulsed (PS) modes. Precipitation time was found to vary with input power of applied ultrasound. X-ray diffraction studies show the formation hexagonal wurtzite phase of nano ZnO but variation in size, strain and lattice parameters was observed in the samples synthesized through CS and PS modes with different input power. Surface morphology of the samples changed significantly with input power of the pulse as observed from scanning electron microscopic results. Well defined and c-axis oriented nanorods and multipodes were observed with power setting of 187.5 W whereas in all other cases no definite morphology was observed. UV absorption studies show higher value of absorbance for ZnO:S. Further, the absorption band becomes sharp for the samples prepared with power setting of 225 W. PL spectra show several bands due to different transitions in the region of 400-780 nm which have been explained in the light of excitonic and defect induced transitions in ZnO.

Elemental analysis of coal and coal ASH by PIXE technique

Coal and coal ash samples were characterized by particle induced X-ray emission spectroscopic technique. Sixteen elements, namely K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, As, Rb, Sr, Y and Pb were quantified in this study. Elements like K, Ca, Ti and Fe were present as major elements, whereas, other elements like V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Rb, Sr and Pb were present in trace level. The enrichment ratio of different ash samples with respect to coal were also estimated and discussed.

Management of severe extra-articular contracture of the elbow by open arthrolysis and a monolateral hinged external fixator

Arthrolysis and dynamic splinting have been used in the treatment of elbow contractures, but there is no standardised protocol for treatment of severe contractures with an arc of flexion < 30 degrees . We present our results of radical arthrolysis with twin incisions with the use of a monolateral hinged fixator to treat very severe extra-articular contracture of the elbow. This retrospective study included 26 patients (15 males and 11 females) with a mean age of 30 years (12 to 60). The mean duration of stiffness was 9.1 months (5.4 to 18) with mean follow-up of 5.2 years (3.5 to 9.4). The mean pre-operative arc of movement was 15.6 degrees (0 degrees to 30 degrees ), with mean pre-operative flexion of 64.1 degrees (30 degrees to 120 degrees ) and mean pre-operative extension of 52.1 degrees (10 degrees to 90 degrees ). Post-operatively the mean arc improved to 102.4 degrees (60 degrees to 135 degrees ), the mean flexion improved to 119.1 degrees (90 degrees to 140 degrees ) and mean extension improved to 16.8 degrees (0 degrees to 30 degrees ) (p < 0.001). The Mayo elbow score improved from a mean of 45 (30 to 65) to 89 (75 to 100) points, and 13 had excellent, nine had good, three had fair and one had a poor result. We had one case of severe instability and one wound dehiscence which responded well to treatment. One case had deep infection with poor results which responded well to treatment. Our findings indicate that this method is very effective in the treatment of severe elbow contracture; however, a randomised controlled study is necessary for further evaluation.

Effects of aluminium exposure on brain glutamate and GABA systems: an experimental study in rats

It has been postulated that the neurotoxic effects of aluminium could be mediated through glutamate, an excitatory amino acid. Hence the effects of aluminium administration (at a dose of 4.2mg/kg body weight daily as aluminium chloride, hexahydrate, intraperitoneally, for 4 weeks) on glutamate and gamma-amino butyrate (GABA), an inhibitory amino acid, and related enzyme activities in different regions of the brain were studied in albino rats. The glutamate level increased significantly in the cerebrum, thalamic area, midbrain-hippocampal region and cerebellum in response to in vivo aluminium exposure. The aluminium insult also caused significant increases in glutamate alpha-decarboxylase activity in all the brain regions. However, on aluminium insult, the GABA content was not significantly changed except in the thalamic area, where it was elevated. On the contrary, the GABA-T activities of all the regions were reduced significantly in all regions except the midbrain-hippocampal region. However, the succinic semi-aldehyde content of all brain regions increased, often significantly. The aluminium-induced modification of the enzyme activities may be either due to the direct impact of aluminium or due to aluminium-induced changes in the cellular environment. The aluminium-induced differential regional accumulation of glutamate or other alterations in enzymes of the glutamate-GABA system may be one of the causes of aluminium-induced neurotoxicity.

The influence of a bupivacaine and fentanyl epidural infusion after epidural fentanyl in patients allowed to ambulate in early labor

Epidural fentanyl after a lidocaine and epinephrine test dose provides adequate analgesia and allows for ambulation during early labor. This study was designed to determine the influence of an epidural infusion of bupivacaine plus fentanyl administered after initiation of epidural labor analgesia with fentanyl. Specifically, we evaluated whether there is an increase in motor block or an increased time to request for further analgesic medication. Fifty-one laboring primigravid women at <5 cm cervical dilation who requested epidural analgesia were enrolled. After a 3-mL epidural test dose of 1.5% lidocaine with epinephrine (5 microg/mL), patients received fentanyl 100 microg via the epidural catheter. They then randomly received either an infusion (10 mL/h) of 0.0625% bupivacaine with fentanyl (3 microg/mL) or an infusion of preservative-free saline. After the administration of the initial analgesic, pain scores and side effects were recorded for each patient at 10, 20, and 30 min, every 30 min thereafter, and at the time of request for additional analgesic medication, by an observer blinded to the technique used. There were no demographic differences between the two groups. The mean duration of analgesia (time from initial dose to request for additional analgesia) was increased in the group that received a continuous infusion of bupivacaine and fentanyl compared with the Saline group (198 +/- 86 vs 145 +/- 50 min; P < 0.009). Side effects were similar between the two groups. No patient in either group experienced any detectable motor block. Fourteen patients chose to ambulate in the Saline group, and 12 patients chose to ambulate in the Infusion group. In early laboring patients, a continuous infusion of 0.0625% bupivacaine infusion with fentanyl (3 microg/mL) prolonged the duration until top-up was required, after epidural fentanyl 100 microg after a lidocaine and epinephrine test dose, and did not cause any clinically detectable motor block.

IMPLICATIONS

A 0.0625% bupivacaine and fentanyl (3 microg/mL) infusion, when added to epidural fentanyl (100 microg), prolongs the analgesic duration without increasing motor block in women in early labor.

Chromium-induced membrane damage: protective role of ascorbic acid

Importance of chromium as environmental toxicant is largely due to impact on the body to produce cellular toxicity. The impact of chromium and their supplementation with ascorbic acid was studied on plasma membrane of liver and kidney in male Wistar rats (80-100 g body weight). It has been observed that the intoxication with chromium (i.p.) at the dose of 0.8 mg/100 g body weight per day for a period of 28 days causes significant increase in the level of cholesterol and decrease in the level of phospholipid of both liver and kidney. The alkaline phosphatase, total ATPase and Na(+)-K(+)-ATPase activities were significantly decreased in both liver and kidney after chromium treatment, except total ATPase activity of kidney. It is suggested that chromium exposure at the present dose and duration induce for the alterations of structure and function of both liver and kidney plasma membrane. Ascorbic acid (i.p. at the dose of 0.5 mg/100 g body weight per day for period of 28 days) supplementation can reduce these structural changes in the plasma membrane of liver and kidney. But the functional changes can not be completely replenished by the ascorbic acid supplementation in response to chromium exposure. So it is also suggested that ascorbic acid (nutritional antioxidant) is useful free radical scavenger to restrain the chromium-induced membrane damage.

Differential responses of certain brain phosphoesterases to aluminium in dietary protein adequacy and inadequacy

The aluminium-induced neurotoxic consequences include, among other factors, dephosphorylation, phosphorylation as well as hyperphosphorylation of specific macromolecules. Accordingly, activities of phosphoesterases were measured in different regions of rat brain, maintained with either adequate or inadequate protein diet, following aluminium exposure. Male Wistar rats weighing 80-100 g were treated with aluminium chloride at a dose of 15% of the LD50 for 4 weeks. In different regions of the brain of aluminium-exposed rats, significant variation in both phosphomonoesterase and phosphodiesterase activities have been recorded. These alterations were found to be varied when the rats were subjected to dietary protein insufficiency. These findings demonstrate the specificity of aluminium on different phosphoesterases. These regional variations may be attributed to the accumulated level of aluminium or may be due to cellular localization of these enzymes and linked to whether the enzymes are compartmentalized with different aluminium hydration species.

Impact of protein malnutrition on subcellular nucleic acid and protein status of brain of aluminum-exposed rats

Nucleic acid and protein content in various cellular fractions of different regions of the brain were investigated in male albino rats following aluminum (Al) exposure (at the dose of 15% of LD50 i.p. for 28 days) on either an adequate or inadequate protein diet. It was observed that there was a decrease in homogenate DNA content in the thalamic area (Th), midbrain-hippocampal region (MH) and cerebellum (CL), but not in the cerebrum (CC) of the protein-restricted group of animals. Increased RNA content was recorded in the ribosomal and soluble fractions of CL of the adequately protein-fed animals compared to pair-fed controls. In the low-protein-fed animals, on the other hand, a decrease in RNA content was observed in the whole homogenate and nuclear fractions of CC, MH and CL, the ribosomal and soluble fractions of MH and CL, and in the mitochondrial fraction of TH. Ribonucleolytic activity was found to be increased only in the Th and CL of the adequately protein-fed group. Protein contents in the subcellular fractions of these four regions remain almost unaltered with the present dose and duration of Al-exposure; only the soluble fraction of CC and microsomal fraction of Th of the low-protein-fed group showed a significant decrease. The results of the present investigation confirm that Al has generally depressive effects on the nucleic acid metabolism of the brain and suggest that these effects are region-specific as well as dependent on dietary protein level. It is further suggested that alterations in the cellular microenvironment, caused by protein malnutrition, may play a significant role in the modification of the effects of Al in the brain.

Transgenic elite indica rice plants expressing CryIAc delta-endotoxin of Bacillus thuringiensis are resistant against yellow stem borer (Scirpophaga incertulas)

Generation of insect-resistant, transgenic crop plants by expression of the insecticidal crystal protein (ICP) gene of Bacillus thuringiensis (Bt) is a standard crop improvement approach. In such cases, adequate expression of the most appropriate ICP against the target insect pest of the crop species is desirable. It is also considered advantageous to generate Bt-transgenics with multiple toxin systems to control rapid development of pest resistance to the ICP. Larvae of yellow stem borer (YSB), Scirpophaga incertulas, a major lepidopteran insect pest of rice, cause massive losses of rice yield. Studies on insect feeding and on the binding properties of ICP to brush border membrane receptors in the midgut of YSB larvae revealed that cryIAb and cryIAc are two individually suitable candidate genes for developing YSB-resistant rice. Programs were undertaken to develop Bt-transgenic rice with these ICP genes independently in a single cultivar. A cryIAc gene was reconstructed and placed under control of the maize ubiquitin 1 promoter, along with the first intron of the maize ubiquitin 1 gene, and the nos terminator. The gene construct was delivered to embryogenic calli of IR64, an elite indica rice cultivar, using the particle bombardment method. Six highly expressive independent transgenic ICP lines were identified. Molecular analyses and insect-feeding assays of two such lines revealed that the transferred synthetic cryIAc gene was expressed stably in the T2 generation of these lines and that the transgenic rice plants were highly toxic to YSB larvae and lessened the damage caused by their feeding.

Efficient transgenic plant regeneration throughAgrobacterium-mediated transformation of Chickpea (Cicer arietinum L.)

Three genotypes of chickpea ICCV-1, ICCV-6 and a Desi (local) variety were tested for plant regeneration through multiple shoot production. The embryo axis was removed from mature seeds, the root meristem and the shoot apex were discarded. These explants were cultured on medium containing MS macro salts, 4X MS micro salts, I35 vitamins, 3.0 mg/1 BAP, 0.004 mg/1 NAA, 3% (w/v) sucrose and incubated at 26(0)C. The explants were transformed withAgrobacterium tumefaciens strain LBA4404 with binary vector pBI121 containing theuidA andnptIl genes. Multiple shoots were repeatedly selected with kanamycin. The selected kanamycin resistant shoots were rooted on MS medium supplemented with 0.05 mg/1 113A. The presumptive transformants histochemically stained positive for GUS. Additionally, nptll assay confirmed the expression ofnptII in kanamycin resistant plants. Transgenic plants were transferred to soil and grown in the green house.

Diagnosis of tuberculous meningitis: a comparative analysis of 3 immunoassays, an immune complex assay and the polymerase chain reaction

OBJECTIVE

To compare 3 immunoassays, an immune complex assay, and an application of the polymerase chain reaction (PCR) for the diagnosis of tuberculous meningitis (TBM).

MATERIAL

Cerebrospinal fluid (CSF) from 33 patients with TBM and from 34 control patients with infectious and non-infectious CNS diseases was analysed.

RESULTS

The antibody immunoassays were either nonspecific or insensitive. However, detection of mycobacterial IgG immune complexes correlated strongly with infection, as they were detected in the CSF from 64% of the patients with TBM compared to only 3 (9%) of the control samples. PCR analysis, using Mycobacterium tuberculosis-specific oligonucleotide primers, also strongly correlated with infection, as DNA was amplified from 54% of the samples from patients with TBM, but from only 2 (6%) of the control samples. Both 'false positive' samples were also positive in the immune complex assay and came from 2 patients with otogenic brain abscesses. It is conceivable that these patients suffered from otogenic tuberculosis with secondary non-mycobacterial meningitis. When combining the immune complex assay with DNA-detection by PCR, 100% of the culture positive and 74% of culture negative samples were found to be positive, while maintaining a high specificity.

CONCLUSION

Parallel analysis to detect mycobacterial immune complexes and M. tuberculosis-specific DNA by PCR from the CSF of patients may offer a sensitive and specific tool for the diagnosis of TBM.

Effects of naloxone infusion in patients with septic shock and renal failure: a limited experience

Septic shock is frequently associated with acute renal failure. Management of these patients becomes complicated if either the renal or systemic hemodynamic derangement cannot be corrected. Although previously large doses of furosemide and naloxone infusion have been used separately in managing these patients, the combination of both agents has not been employed. We therefore report our limited experience with this combined treatment in 5 patients with septic shock, of which 4 had acute renal failure.

Plant regeneration through somatic embryogenesis from suspension culture-derived protoplasts of Paspalum scrobiculatum L

Protoplasts were released from embryogenic suspension culture of Paspalum scrobiculatum and cultured in either liquid or semisolid KM medium supplemented with 2,4-D in the dark at 24°C with or without a feeder layer. Cell wall formation was observed in 75% of the plated protoplasts. Microcolonies developed after 10 d of culture, which in turn formed callus upon transfer to M-2 medium (Nayak and Sen, 1989). The highest plating effeciency (ca 7%) was obtained in thin-layer liquid culture. The macrocalli formed somatic embryos which regenerated to plantlets. The plantlets were grown to flowering plants upon transfer to soil.