Coordination between the Ndc80 complex and dynein is essential for microtubule plus-end capture by kinetochores during early mitosis

Mitotic kinetochores are initially captured by dynamic microtubules via a "search-and-capture" mechanism. The microtubule motor, dynein, is critical for kinetochore capture as it has been shown to transport microtubule-attached chromosomes toward the spindle pole during prometaphase. The microtubule-binding nuclear division cycle 80 (Ndc80) complex that is recruited to kinetochores in prophase is known to play a central role in forming kinetochore-microtubule (kMT) attachments in metaphase. It is not yet clear, however, how Ndc80 contributes to initial kMT capture during prometaphase. Here, by combining CRISPR/Cas9-mediated knockout and RNAi technology with assays specific to study kMT capture, we show that mitotic cells lacking Ndc80 exhibit substantial defects in this function during prometaphase. Rescue experiments show that Ndc80 mutants deficient in microtubule-binding are unable to execute proper kMT capture. While cells inhibited of dynein alone are predominantly able to make initial kMT attachments, cells co-depleted of Ndc80 and dynein show severe defects in kMT capture. Further, we use an in vitro total internal reflection fluorescence microscopy assay to reconstitute microtubule capture events, which suggest that Ndc80 and dynein coordinate with each other for microtubule plus-end capture and that the phosphorylation status of Ndc80 is critical for productive kMT capture. A novel interaction between Ndc80 and dynein that we identify in prometaphase extracts might be critical for efficient plus-end capture. Thus, our studies, for the first time, identify a distinct event in the formation of initial kMT attachments, which is directly mediated by Ndc80 and in coordination with dynein is required for efficient kMT capture and chromosome alignment.

A potential role of mesenchymal stem cells derived from human umbilical cord blood in ameliorating psoriasis-like skin lesion in the rats

BACKGROUND

Psoriasis is a common autoimmune inflammatory skin disease, with no clear cause, treated with topical agents and phototherapy to conventional immunosuppressant drugs and biologic agents. Stem cell therapy has showed significant interest in regenerative medicine. The aim of this study was to use mesenchymal stem cell (MSC) therapy compared to the topical application of the standard conventional corticosteroid cream.

MATERIALS AND METHODS

40 male adult albino rats were used, divided into 4 groups, 10 rats each. Group I (control), Group II (Psoriasis-like lesions induced by usage of Aldara cream), Group III (treated with Betamethasone) and Group IV (treated with mesenchymal stem cells). Specimens were stained with Hematoxylin & Eosin, Masson's trichrome, immune-histochemical technique for CD4, CD8 and CD31. Ultra-sections were prepared for transmission electron microscope examination.

RESULTS

MSCs demonstrated efficacy in reduction of disease severity in the form of uniform epidermal thickness covered by a very thin keratin layer. Normally- arranged layers of epidermal layers, with a clear border demarcation was seen between the epidermis and the dermis with apparently intact basement membrane. TEM showed absence of gaps between the tightly connected cells of the basal layer and the resting basement membrane.

CONCLUSIONS

application of MSCs raises hope for developing a new, safe and effective therapy for psoriatic patients, avoiding the side effects of betamethasone.

Lateral attachment of kinetochores to microtubules is enriched in prometaphase rosette and facilitates chromosome alignment and bi-orientation establishment

Faithful chromosome segregation is ensured by the establishment of bi-orientation; the attachment of sister kinetochores to the end of microtubules extending from opposite spindle poles. In addition, kinetochores can also attach to lateral surfaces of microtubules; called lateral attachment, which plays a role in chromosome capture and transport. However, molecular basis and biological significance of lateral attachment are not fully understood. We have addressed these questions by focusing on the prometaphase rosette, a typical chromosome configuration in early prometaphase. We found that kinetochores form uniform lateral attachments in the prometaphase rosette. Many transient kinetochore components are maximally enriched, in an Aurora B activity-dependent manner, when the prometaphase rosette is formed. We revealed that rosette formation is driven by rapid poleward motion of dynein, but can occur even in its absence, through slow kinetochore movements caused by microtubule depolymerization that is supposedly dependent on kinetochore tethering at microtubule ends by CENP-E. We also found that chromosome connection to microtubules is extensively lost when lateral attachment is perturbed in cells defective in end-on attachment. Our findings demonstrate that lateral attachment is an important intermediate in bi-orientation establishment and chromosome alignment, playing a crucial role in incorporating chromosomes into the nascent spindle.

T4 lysozyme fused with cellulose-binding module for antimicrobial cellulosic wound dressing materials

AIMS

Bacterial infection is a major challenge in wound care. Antimicrobial wound dressings are of great value for treating wound infections. Endolysins are evolving as a new class of antimicrobials with multiple applications. This study describes the production and evaluation of T4 lysozyme (T4Lyz), product of gene e of the T4 bacteriophage, fused with Cellulose Binding Module (CBM) for facile immobilization to cellulosic wound dressing.

METHODS AND RESULTS

Genes encoding T4Lyz-CBM and T4Lyz were cloned and expressed in Escherichia coli and the enzymes were purified by cation exchange chromatography. While the CBM tag did not alter the optimum pH and stability features of T4Lyz, the lytic activity of the fusion protein was lowered. The bactericidal activity of T4Lyz-CBM, determined by viable count plating assay after 1 h incubation with Micrococcus lysodeikticus was 97·5% with 10 μg ml(-1) , and 99·96% and 95% for E. coli and Pseudomonas mendocina, respectively, with 200 μg ml(-1) enzyme. T4Lyz-CBM was immobilized to wound dressing gauze with a capacity of 5·5 μg mg(-1) matrix, whereas the unmodified T4Lyz did not exhibit any binding. The immobilized protein retained its bactericidal activity against Gram-positive and Gram-negative bacteria. Both free and immobilized T4Lyz-CBM, after heat denaturation, retained their bactericidal activities against Gram-negative bacteria only. The immobilized enzyme exhibited higher stability than the free enzyme when stored in dry form or in the presence of polyol stabilizers.

CONCLUSION

Tagging T4Lyz with CBM provides a facile, irreversible binding to cellulosic wound dressing while retaining its activity. This approach may be suitable even for other antimicrobial enzymes and -peptides.

SIGNIFICANCE AND IMPACT OF THE STUDY

The spread of antibiotic resistance requires innovative strategies for discovery and development of effective antimicrobial alternatives. This report presents a novel strategy for producing antimicrobial wound dressing materials.

CLIP-170 tethers kinetochores to microtubule plus ends against poleward force by dynein for stable kinetochore-microtubule attachment

The cytoplasmic linker protein (CLIP)-170 localizes to kinetochores and is suggested to function in stable attachment of kinetochores to microtubule ends. Here we show that defects in kinetochore-microtubule attachment and chromosome alignment in CLIP-170-depleted cells were rescued by co-depletion of p150glued, a dynactin subunit required for kinetochore localization of CLIP-170. CLIP-170 recruited p150glued to microtubule ends. Kinetochore localization at microtubule ends was perturbed by CLIP-170 depletion, which was rescued by co-depleting p150glued. Our results imply that CLIP-170 tethers kinetochores to microtubule ends against the dynein-mediated poleward force to slide kinetochores along microtubules, facilitating the stable kinetochore attachment to microtubules.

CLIP-170 recruits PLK1 to kinetochores during early mitosis for chromosome alignment

The cytoplasmic linker protein (CLIP)-170, an outer kinetochore protein, has a role in kinetochore-microtubule attachment and chromosome alignment during mitosis. However, the mechanism by which CLIP-170 is involved in chromosome alignment is not known. Here, we show that CLIP-170 colocalizes with Polo-like kinase 1 (PLK1) at kinetochores during early mitosis. Depletion of CLIP-170 results in a significant reduction in PLK1 recruitment to kinetochores and causes kinetochore-fiber (K-fiber) instability and defects in chromosome alignment at the metaphase plate. These phenotypes are dependent on the phosphorylation of CLIP-170 at a CDK1-dependent site, T287, as ectopic expression of wild-type CLIP-170, but not the expression of a non-phosphorylatable mutant, CLIP-170-T287A, restores PLK1 localization at kinetochores and rescues K-fiber stability and chromosome alignment in CLIP-170-depleted cells. These data suggest that CLIP-170 acts as a novel recruiter and spatial regulator of PLK1 at kinetochores during early mitosis, promoting K-fiber stability and chromosome alignment for error-free chromosome segregation.

Site selectivity in reactions of hydrazonoyl halides with heterocycles containing amino and thione groups leading to fused heterocycles of potential antimicrobial activity

Reaction of hydrazonoyl halides with 6-(benzylidenamino)-2-thioxo-2,3-dihydro-1H-pyrimidin-4-one and 2,3-diaminoquinazolin-4-one site-selectively afforded 3-substituted-7-(benzylidenamino)-1-phenyl-[1,2,4]triazolo[4,3-a]-pyrimidin-5(1H)-ones, [1,2,4,5]tetrazino[6,1-b]quinazolin-6(4H)-one, and 3-methyl-2-(4-substituted-phenylhydrazo)-[1,2,4]triazino[3,2-b]quinazolin-10-ones in good yields. The structures of the newly synthesized compounds were elucidated by chemical evidence and their IR, 1H, 13C NMR, and MS spectra. Furthermore, some of the products were screened against different strains of bacteria and fungi.

Precipitating factor of seizure in epilepsy: experience in a tertiary care hospital

Patients with epilepsy experience recurrent, unprovoked seizures. In most of the cases seizure occurs spontaneously, but there may be association with various triggers. These triggers may act as seizure precipitating factors (SPFs). This study was done to find out the most common SPFs and their relationship to different types epileptic patients attending a tertiary care hospital in Bangladesh. This cross sectional study was carried out in specialized epilepsy weekly outdoor clinic and Medicine outpatient department (OPD) of Dhaka Medical College Hospital from January 2008 to July 2011, which included 1168 epilepsy patients. All patients attending the clinic were included in the study. Epilepsy syndromes were broadly classified into four categories using the classification system of international league against epilepsy (ILAE) namely, generalized epilepsy (GE), localization related epilepsy (LRE), symptomatic and unclassified. Each patient was evaluated and classified by consultant neurologist. All participants were interviewed through a predesigned close ended questionnaire that included a long list of 30 precipitating factors. Among all the patients 71.5% were male, with most common age group 11-20 years (36.8%). About 62% could indentify at least one precipitator. Excitation (25.2%) was the most common SPF reported by patients followed by emotional stress in 17.7%. Fever precipitated seizure in 16.4% of the subjects. A good number of them (15.5%) noticed that whenever there was sleep deprivation, they had an attack of epilepsy. However, drug withdrawal, playing outside and head trauma were also common among the patients, about 11.7%, 11.3% and 8.4% respectively. Most of the patients can identify their seizure precipitant and clustering of many SPFs suggests a common patho-physiologic mechanism for these triggers. Excitation, sleep deprivation, fever, watching television and head trauma showed a strong association with generalized epilepsy. Patients with seizure disorder should be evaluated for presence of SPFs, because identification of these might help in proper management of epilepsy.

Progress achieved in the elimination of schistosomiasis from the Jazan region of Saudi Arabia

Among the inhabitants of the Jazan region of Saudi Arabia, the prevalence and intensity of Schistosoma haematobium infection have been kept very low for several years, by sustained control efforts. The success of the interventions, which were based on case finding, the treatment of infected individuals, and the chemical and environmental control of freshwater snails, led, in mid-2002, to a strategy to eliminate human infection with S. haematobium from Jazan. The strategy, which was based on regular chemotherapy, snail control (made easier by the focality of transmission in the area) and health education, with screening at primary-healthcare centres, by mobile teams and at diagnostic units, appears to have been successful. No infected snails can now be found in the region and new cases of human infection with S. haematobium are only being detected in border villages (and are attributed to infections beyond the region, in areas where active transmission is still taking place). Total elimination appears possible if the health authorities in neighbouring areas can be persuaded to adopt a similar strategy of control.

A creeper, Coccinia indica, has anti-hyperglycaemic and anti-ureogenic effects in diabetic rats

OBJECTIVE

To explore how ethanolic extract of Coccinia indica affects normal and diabetic rats.

METHODS

The case-controlled animal study was conducted in June 2008 at the Department of Biochemistry and Molecular Biology, University of Dhaka, Bangladesh. Two groups of 10 male rats each - one streptozotocin-induced diabetics and the other normal - were fed orally aqueous suspension of residue extracted from C. indica leaves with 60% ethanol after 18 hours of fasting. After 90 minutes of oral administration, the rats were sacrificed, and blood level of glucose and free fatty acids and hepatic arginase activity were analysed.

RESULTS

The blood sugar level had significantly decreased by 23% (p <0.01) and 28% (p <0.001) in the normal and diabetic rats. Level of blood-free fatty acid was depressed by 15% (p <0.01) and 25% (p <0.001) in the two groups respectively. Moreover, the activity of hepatic arginase, a key urea cycle enzyme, was significantly depressed by 14% (p < 0.05) and 22% (p < 0.02) in the normal and diabetic groups.

CONCLUSION

Results suggested that C. indica extract had anti-hyperglycaemic and anti-ureogenic effects on the diabetic rats as judged by the decreased level of blood glucose and fatty acid and hepatic arginase activity.

Nucleophosmin is required for chromosome congression, proper mitotic spindle formation, and kinetochore-microtubule attachment in HeLa cells

Nucleophosmin (NPM) is an abundantly expressed multifunctional nucleolar phosphoprotein. Here we show that depletion of NPM by RNA interference causes defects in cell division, followed by an arrest of DNA synthesis due to activation of a p53-dependent checkpoint response in HeLa cells. Depletion of NPM leads to mitotic arrest due to spindle checkpoint activation. The mitotic cells arrested by NPM depletion have defects in chromosome congression, proper mitotic spindle and centrosome formation, as well as defects in kinetochore-microtubule attachments. Loss of NPM thus causes severe mitotic defects and delayed mitotic progression. These findings indicate that NPM is essential for mitotic progression and cell proliferation.

Fibrillarin, a nucleolar protein, is required for normal nuclear morphology and cellular growth in HeLa cells

Fibrillarin is a key small nucleolar protein in eukaryotes, which has an important role in pre-rRNA processing during ribosomal biogenesis. Though several functions of fibrillarin are known, its function during the cell cycle is still unknown. In this study, we confirmed the dynamic localization of fibrillarin during the cell cycle of HeLa cells and also performed functional studies by using a combination of immunofluorescence microscopy and RNAi technique. We observed that depletion of fibrillarin has almost no effect on the nucleolar structure. However, fibrillarin-depleted cells showed abnormal nuclear morphology. Moreover, fibrillarin depletion resulted in the reduction of the cellular growth and modest accumulation of cells with 4n DNA content. Our data suggest that fibrillarin would play a critical role in the maintenance of nuclear shape and cellular growth.

Biological treatment of industrial wastes in a photobioreactor

An algal-bacterial consortium was tested for the treatment from a coke factory. A Chlorella vulgaris strain and a phenol-degrading Alcaligenes sp. were first isolated from the wastewater treatment plant to serve as inocula in the subsequent biodegradation tests. Batch tests were then conducted with samples from the real wastewater or using a synthetic wastewater containing 325 mg phenol/l and 500 mg NH4+/l as target pollutants. Direct biological treatment of the real wastewater was not possible due to the toxicity of organic compounds. Activated carbon adsorption and UV(A-B)-irradiation were efficient in detoxifying the effluent for subsequent biological treatment as inoculation of pretreated samples with the algal-bacterial consortium was followed by complete phenol removal and NH4+ removal of 45%. Complete phenol removal and 33% NH4+ removal were achieved during the fed-batch treatment of artificial wastewater at 6 d hydraulic retention time (HRT). Under continuous feeding at 3.6 d HRT, phenol and NH4+ removal dropped to 58 and 18%, respectively. However, complete phenol removal and 29% NH4+ removal were achieved when 8 g NaHCO3/l was added to the artificial wastewater to enhance algal growth. This study confirms the potential of solar-based industrial wastewater treatment based on solar-based UV pretreatment followed by algal-bacterial biodegradation.

Use of the buccal fat pad in the reconstruction and prosthetic rehabilitation of oncological maxillary defects

We evaluated the effectiveness of the buccal fat pad as a pedicled flap for intraoral reconstruction after partial maxillectomy for neoplastic disease in 24 patients, and subsequently, in providing support for a denture. In all patients the buccal fat pad was covered with a split-skin graft and an acrylic plate. There was complete healing of the buccal fat pad flap within 6 weeks in 18 patients with no major complications, and minimal effects on speech and eating. In six cases there was partial dehiscence of the flap, which healed spontaneously in one patient and was repaired with local flaps in two others. There were no cases of complete breakdown of the flap. Eight patients so far have been rehabilitated with small dentures. In conclusion, the buccal fat pad flap is a simple, quick, and reliable method of reconstruction of small to medium-sized posterior maxillary alveolar defects.

Congenital atresia of the orifice of the submandibular duct: a report of 2 cases and review

Two infants presented with unilateral cystic swellings in the floor of the mouth as a result of imperforate submandibular ducts. This is thought to result from a congenital failure of canalization of the terminal end of the duct. Both cases responded to simple incision and decompression of the fluid-filled duct. Early treatment is important to avoid feeding difficulties and to prevent later complications such as ranula or sialadenitis.

Fractalkine: a novel angiogenic chemokine in rheumatoid arthritis

Angiogenesis is an important aspect of the vasculoproliferation found in the rheumatoid arthritic (RA) pannus. We have previously implicated members of the CXC chemokine family as potent angiogenic mediators in RA. We investigated the possibility that the sole member of the CX(3)C chemokine family, fractalkine (fkn), induces angiogenesis and that fkn might mediate angiogenesis in RA. Recombinant human fkn significantly induced migration of human dermal microvascular endothelial cells (HMVECs), a facet of the angiogenic response, in the pmol/L range in a concentration-dependent manner (P < 0.05). Fkn also induced the formation of significantly more endothelial tubes on Matrigel than did a negative control (P < 0.05). Fkn significantly induced 2.3-fold more blood vessel growth than control in the in vivo Matrigel plug assays (P < 0.05). We identified HMVEC expression of the fkn receptor, CX(3)CR1. Next, we determined if RA synovial fluid (SF)-induced angiogenesis was fkn-dependent. SFs from six RA patients immunodepleted of soluble fkn induced 56% less migration of HMVECs than did sham-depleted RA SFs (P < 0.05). In vivo, immunodepletion of fkn from six RA SFs significantly inhibited their angiogenic activity in Matrigel plug assays (P < 0.05). Immunodepletion of fkn from five RA synovial tissue homogenates inhibited their ability to induce angiogenesis in in vivo Matrigel plug assays (P < 0.05). These results establish a new function for fkn as an angiogenic mediator and suggest that it may mediate angiogenesis in RA.

Clinical and radiological evidence to support superficial parotidectomy as the treatment of choice for chronic parotid sialadenitis: a retrospective study

We present a retrospective series of 23 consecutive parotidectomies, over a 10-year period (1989-1999) for 22 patients with chronic sialadenitis unresponsive to conservative measures. There were 10 male and 12 female patients. Mean age was 52 years (range 12-72), and mean duration of symptoms 4.5 years (range 8 months-30 years). All patients had preoperative sialography and 2 had computed tomography to exclude a neoplasm. A complete superficial parotidectomy with preservation of the main duct was done in all cases. Fifteen patients developed temporary facial nerve weakness postoperatively and 7 developed Frey's syndrome. There were no cases of permanent facial nerve palsy. Nineteen patients reported complete resolution of their symptoms and 3 patients had mild persisting symptoms that did not necessitate any further treatment. Histologically there was evidence of sialadenosis in one case and benign lymphoepithelial lesion in another; the others showed evidence of chronic sialadenitis of varying degrees of severity. Fifteen patients had postoperative sialograms, of which 11 showed evidence of some filling of residual parotid gland parenchyma and in 8 patients there was filling of a normal-looking accessory lobe. In this series, superficial parotidectomy with preservation of the main duct was safe and effective, with minimal long-term complications, for most patients with chronic parotid sialadenitis that was unresponsive to conservative measures and, in some patients, it allowed some preservation of function. The potential damage to the facial nerve and the cosmetic problems associated with a total or near-total parotidectomy were avoided.

Evidence of IL-18 as a novel angiogenic mediator

Angiogenesis, or new blood vessel growth, is a key process in the development of synovial inflammation in rheumatoid arthritis (RA). Integral to this pathologic proliferation are proinflammatory cytokines. We hypothesized a role for IL-18 as an angiogenic mediator in RA. We examined the effect of human IL-18 on human microvascular endothelial cell (HMVEC) migration. IL-18 induced HMVEC migration at 1 nM (p < 0.05). RA synovial fluids potently induced endothelial cell migration, but IL-18 immunodepletion resulted in a 68 +/- 5% decrease in HMVEC migration (p < 0.05). IL-18 appears to act on HMVECs via alpha(v)beta(3) integrin. To test whether IL-18 induced endothelial cell tube formation in vitro, we quantitated the degree of tube formation on Matrigel matrix. IL-18, 1 or 10 nM, resulted in a 77% or 87% increase in tube formation compared with control (p < 0.05). To determine whether IL-18 may be angiogenic in vivo, we implanted IL-18 in Matrigel plugs in mice, and IL-18 at 1 and 10 nM induced angiogenesis (p < 0.05). The angiogenesis observed appears to be independent of the contribution of local TNF-alpha, as evidenced by adding neutralizing anti-TNF-alpha Ab to the Matrigel plugs. In an alternative in vivo model, sponges embedded with IL-18 or control were implanted into mice. IL-18 (10 nM) induced a 4-fold increase in angiogenesis vs the control (p < 0.05). These findings support a novel function for IL-18 as an angiogenic factor in RA and may elucidate a potential therapeutic target for angiogenesis-directed diseases.

Diagnosis of deep vein thrombosis in the leg by using colour coded duplex sonography

BACKGROUND

Deep Vein Thrombosis (DVT) is regarded rare [not readable: see text] Asia. There is no documentation of the incidence of DVT in Pakistan. Clinical diagnosis of Deep Vein Thrombosis is inaccurate. Venography is the most reliable method of diagnosis, but it has several disadvantages. Many non-invasive diagnostic methods have therefore been developed in the past decade. Of these only duplex sonography has comparable accuracy.

METHODS

We studied 100 cases of suspected DVT by using colour coded duplex sonography. We report the results of a prospective study in patients with suspected deep vein thrombosis evaluated by both colour coded Doppler sonography and venography.

CONCLUSION

We conclude that colour coded duplex sonography is a highly accurate, simple, non-invasive method for detecting femoropopliteal thrombosis. Additional venography is not necessary. Its value in diagnosing isolated calf vein thrombosis remains to be established.

Delay in the diagnosis and prognosis of caecal carcinoma--a study of 20 cases

BACKGROUND

Caecum is the dilated part of the right colon situated in the right iliac fossa, therefore the etiology of this cancer is similar to those of the rest of the colon. Caecal carcinoma is more common in developed countries but it is not a rare disease in underdeveloped countries. This is more common in high socio-economic people who use less fibrous and purified diet. With improvement in health education and social status of the people of Pakistan, there is an emerging trend of Westernization in our society. This may increase the incidence of cancer in Pakistan. Carcinoma of caecum is curable disease is diagnosed early and treated. If we are aware of the pathogenesis, etiology, clinical presentation and management of the disease, we can offer a lot to these patients by diagnosing the caecal carcinoma at an earlier stage, this was the aim of this study.

METHODS

20 cases (15 males and 5 females) of Carcinoma of Caecum were studied from January 1997 to December 1999. Out of these six patients presented in emergency ward, 2 as acute appendicitis and 4 as intestinal obstruction. After routine non-specific investigations, our specific investigations included USG abdomen, barium contrast studies and colonoscopy, Barium study and USG remained of primary importance.

RESULTS

Most of the patients were between age 45-65 years, oldest patient being 80 years old and the youngest was of only 30 years. Most of the patients presented as mass in the right iliac fossa and only some patients as intestinal obstruction. Right hemicolectomy with primary ileo-transverse anastomosis was our standard surgical procedure and was done in about 14 cases. But in some cases ileo-transverse by-pass operation was done as the growth was locally advanced. However, only the omental biopsy was taken in the cases where carcinoma was too advanced.

CONCLUSIONS

We think that our sociodemographic factors put a hindrance in detection of this carcinoma at early stages and therefore curative procedures are difficult to bear good results.

IL-4 adenoviral gene therapy reduces inflammation, proinflammatory cytokines, vascularization, and bony destruction in rat adjuvant-induced arthritis

IL-4 is a cytokine with anti-inflammatory properties on activated macrophages. Rheumatoid arthritis, an autoimmune inflammatory disease, is characterized by a paucity of IL-4 and an abundance of synovial macrophage-derived mediators. Herein, the effect of a single injection of adenovirus-producing rat IL-4 (AxCAIL-4) or a control virus with no inserted gene was compared with the effect of PBS injection into rat ankles. Ankles were injected before arthritis onset or at maximal inflammation. Preventatively, AxCAIL-4 reduced adjuvant-induced arthritis (AIA)- and/or AIA/adenoviral-induced ankle inflammation, decreasing articular index scores, ankle circumferences, paw volumes, radiographic scores, mean levels of monocyte chemoattractant protein-1, the number of inflammatory cells, and the number of synovial blood vessels. Therapeutically, AxCAIL-4 also decreased ankle circumferences and paw volumes in comparison with a control virus with no inserted gene and PBS groups. After arthritis onset, mean levels of TNF-alpha, IL-1beta, macrophage inflammatory protein-2, and RANTES were decreased in AxCAIL-4 rat ankle homogenates compared with PBS-treated homogenates. Thus, increased expression of IL-4 via gene therapy administered in a preventative and/or therapeutic manner reduced joint inflammation, synovial cellularity, levels of proinflammatory cytokines, vascularization, and bony destruction in rat AIA, suggesting that a similar treatment in humans may be beneficial.

Treatment with sulfasalazine or sulfapyridine, but not 5-aminosalicyclic acid, inhibits basic fibroblast growth factor-induced endothelial cell chemotaxis

OBJECTIVE

Rheumatoid arthritis (RA) is characterized by leukocyte recruitment and angiogenesis. We investigated the effects of sulfasalazine (SSZ) and its metabolites, sulfapyridine (SP) and 5-aminosalicylic acid (5-ASA), on components of angiogenesis, namely, endothelial cell (EC) chemotaxis and proliferation, as well as on EC chemokine and soluble adhesion molecule expression.

METHODS

SSZ, SP, and 5-ASA were assayed for their effects on basic fibroblast growth factor (bFGF)-induced human dermal microvascular endothelial cell (HMVEC) chemotaxis and proliferation. EC were plated on Matrigel to assess the effect of SSZ on EC tube formation. Enzyme-linked immunosorbent assays were performed to determine changes in HMVEC production of interleukin-8 (IL-8), monocyte chemoattractant protein-1 (MCP-1), growth-related oncogene alpha (GROalpha), epithelial neutrophil-activating peptide 78 (ENA-78), soluble E-selectin (sE-selectin), and soluble intercellular adhesion molecule 1 (sICAM-1) upon treatment with SSZ or its metabolites.

RESULTS

HMVEC incubated with SSZ or SP exhibited reduced bFGF-induced chemotaxis (59%, [n = 7] and 22%, [n = 3], respectively) (P<0.05). SSZ and SP decreased basal HMVEC proliferation, while 5-ASA increased proliferation (P<0.05; [n = 5]). SSZ decreased bFGF-induced HMVEC proliferation (P<0.05 [n = 5]). SSZ inhibited phorbol 12-myristate 13-acetate-induced HMVEC tube formation (P<0.05; [minimum n = 5]). Tumor necrosis factor alpha-stimulated HMVEC shedding of sICAM-1 was reduced by incubation with either SSZ (19%) or 5-ASA (23%) (P<0.05; [n = 6]). SP inhibited cytokine-stimulated HMVEC expression of IL-8 and MCP-1 (P<0.05; [n = 4]). Neither SSZ nor its metabolites had any effect on HMVEC production of sE-selectin, GROalpha, or ENA-78.

CONCLUSION

These results demonstrate that SSZ and its metabolite SP may affect the pathogenesis of RA by inhibiting EC chemotaxis, proliferation, tube formation, and expression of sICAM-1, IL-8, and MCP-1.

Integration of schistosomiasis-control activities into the primary-health-care system in the Gizan region, Saudi Arabia

A few decades ago, the prevalence of Schistosoma haematobium infection in the human inhabitants of the Gizan region of Saudi Arabia was very high (43%-91%). A vertical programme for the control of the disease, by case finding, treatment of infected individuals and by chemical snail control, was begun in 1974 and led to significant reductions in prevalence in most areas. In 1989 the control activities were gradually integrated into the primary-health-care (PHC) system. Several schools in the area recently participated in the detection of ova (among schoolchildren and neighbouring communities) and organized health-education sessions. The records taken during the vertical and PHC programmes indicate that there were more diagnoses and higher chemotherapy coverage in the latter. The PHC programme has maintained the overall prevalence of infection at an extremely low level (< 1%) and the infection has been completely eradicated in several areas. The participation of schools proved to be particularly useful in terms of population coverage and health education.

Serum LDH and ALP isozyme activities in mice bearing solid Ehrlich carcinoma and/or treated with the maximum tolerated dose (MTD) of aloin

Determination of total LDH and ALP activities and their isozyme patterns in the sera of normal and tumour-bearing animals treated with aloin, a natural anthraquinone with potential antitumour activity, was carried out at 3, 6 and 9 weeks of treatment. Treatment of normal mice with the MTD of aloin (50 mg/Kg b.w.) showed non-significant changes in serum total LDH and ALP activities along with their isozymes throughout the experimental periods. In untreated tumour-bearing animals, serum LDH activity and its isozymes: LDH1-LDH5 showed highly significant increases (192, 32.4, 25.2, 24.7, 29.2 and 30.6%, respectively) after 3 weeks. Highly significant inhibition was recorded in serum total ALP activity and its intestinal and bone isozymes (64, 100 and 56%, respectively), while liver ALP isozyme was increased by 82.3%. Treatment of tumour-bearing mice with the MTD of aloin manifested a significant gradual improvement in both enzyme activities and their isozymes, which were normalized at the end of the experiment (9 weeks), with the exception of intestinal ALP isozyme. All results were reported in comparison to the normal control group.

Falls in the elderly

Finally, we conclude with a reminder that the causes of falls in the elderly are multifactorial and that some of these factors may be summative. Most falls result from interaction of intrinsic and extrinsic (environmental) factors. In the Emergency Department, it is very important to take a detailed history of the circumstances leading to the fall and to perform a thorough physical examination. Every attempt should be made to identify predisposing factors for the fall and for preventive measures to be initiated. These may include geriatric consultation or a home visit to evaluate home environment. There is a great need for additional research in this field. Falls are one of the syndromes common in the elderly that deserve more careful attention and are considered amenable to both primary and secondary prevention measures.

Domestic and wild animals naturally infected with Schistosoma mansoni in the Gezira Irrigated Scheme, Sudan

Domestic and wild animals were examined for natural infection with human schistosomiasis in Northern Gezira, Sudan. Postmortem examination of animals in a number of slaughterhouses revealed no infections in either sheep or goats but Schistosoma mansoni worms were found in two of the 98 cattle examined. Nile rats (Arvicanthus niloticus) were trapped and stray dogs were shot and examined for evidence of schistosome infection. The infection rate in Nile rats was 4.9% (8/164) and in dogs 27.3% (15/55) but whereas viable eggs were found in the excreta and tissues of the rats no eggs could be found in dog faeces. In the laboratory nine puppies were each exposed to 10 000 cercariae but there was no evidence that the infection had taken. It is concluded that A. niloticus, present in large numbers and often found in or near the canals, may be involved in S. mansoni transmission and could act as reservoir hosts, but that dogs are probably infected only in exceptional situations and are unlikely to play a major role in S. mansoni transmission.

Marking snails with nail varnish as a field experimental technique

The use of nail varnish to mark snails for release and recapture in aquatic habitats in the Gezira Irrigation Canals has been evaluated. The nail varnish withstood immersion in canal water and adhered to the snail shell. The recovery of marked snails from a backwater site in a slow moving canal was satisfactory and indicated the usefulness of the technique in predicting changing patterns of immigration and emigration of snails. The method may also indicate ecological changes which affect the stability and mobility of snail populations and yield data on growth rates and longevity.

A field trial using praziquantel (BiltricideR) to treat Schistosoma mansoni and Schistosoma haematobium infection in Gezira, Sudan

A field trial was conducted in the Gezira, Sudan, to evaluate the acceptability and efficacy of praziquantel, a new schistosomicide. In one Arab village 350 patients with Schistosoma mansoni were randomly assigned to two treatment groups and given 1 X 40 mg kg-1 (Group A) or 2 X 20 mg kg-1 given four to six hours apart (Group B). In two small settlements (camps) 2 km distant from the Arab village 38 patients with S. mansoni and 43 with concurrent S. mansoni and S. haematobium infections were given 1 X 40 mg kg-1. Side effects were mild and limited to the first 24 hours after treatment. The main complaints were abdominal pain, diarrhoea, urticaria and/or vomiting and were most common in the camp residents (79%) with 60% of Group A and 45% of Group B having one or more side effects. One month after treatment 'cure' rates were: Camps 63%, Group A 84% and Group B 96%, and the reduction in egg output was over 95%. After 12 months re-infection was greater in the camps. As there was no significant difference in the egg output reduction between the two treatment regimes, praziquantel is recommended for mass chemotherapy in Gezira at the logistically simpler regimen of 1 X 40 mg kg-1.

An assessment of anti-schistosomal treatment on physical work capacity

Acting as their own controls, village subjects from the Gezira are of the Sudan with relatively high levels of schistosomiasis infection were first tested in an exercise laboratory in Khartoum and the tests were then repeated after a period of about 1 yr during which time the subjects were treated with hycanthone and periodically monitored to ensure that they had remained free of the disease. In the meantime they were also given anti-malarial prophylaxis. Laboratory tests showed a significant improvement in physiological work capacity of up to 20% after treatment compared with untreated controls. An overall improvement in pulmonary function, particularly forced vital capacity, was observed as well as a significant increase in mean haemoglobin concentration by 1.1 g/100 ml of blood in the treated group. Apart from these improvements in physical working capacity, the treated subjects subjectively felt better after the exercise tests, as expressed by the disappearance of fatiguability.

The role of field irrigation canals in the transmission of Schistosoma mansoni in the Gezira Scheme, Sudan

This study was carried out to determine the importance of small field irrigation canals (abu eshreens)-of which there are over 22 000 in the Gezira Scheme- in the transmission of schistosomiasis. The observations were made during a 12-month period, November 1976-November 1977. The results indicated that during the 4-year crop rotation the abu eshreens supported snail populations in only two seasons, when they were irrigating crops of either, cotton or groundnuts. Thus, when agricultural labourers built temporary dwellings on the abu eshreen banks during these periods, the probability of finding infected snails was high. The maximum risk periods occurred during vegetable harvesting (including groundnuts) (October-December) and in the cotton picking season (January-April). Certain special situations lead to some abu eshreens playing an even greater and more predictable role in transmission. These occur when abu eshreens: (a) irrigate eucalyptus or fruit trees; (b) irrigate a block inspector's garden; or (c) are situated very close to permanent villages. Possible control measures to reduce the transmission potential of abu eshreens are discussed. These include improved maintenance and the use of either focally sprayed or slow-release molluscicides.

Studies on the enzyme linked immunosorbent assay (ELISA) test for Schistosoma mansoni infections

Extensive studies of the use of the ELISA test for the detection of antibodies in Schistosoma mansoni infections are described. A method has been evolved for the determination of the optimum value for the reference serum endpoint. In chimpanzees infected with S. mansoni a crude egg antigen detected antibodies earlier in the infection than did a worm antigen and was generally more reactive. The ELISA test, using the egg antigen, has been applied to sera from populations infected with S. mansoni, with other human schistosomes, or with helminth infections other than schistosomiasis. The ELISA test was as sensitive as the IFAT and CFT, but more specific. However, many cross-reactions occurred in infections with other human (and with animal) schistosomes, although to a lesser extent with other helminths. In surveys in the Sudan the use of blood collected on absorbent paper was only slightly less sensitive for the detection of antibodies than sera, and this technique showed that the prevalence of infection was higher than that measured by stool examination alone. Possible future developments are discussed with a view to improving sensitivity and specificity both for clinical and epidemiological work.

Energy expenditure and physiological performance of Sudanese cane cutters

The thermal and exercise tolerances of 165 Sudanese cane cutters were measured in the laboratory and related to work performance and productivity in the cane fields. The results showed that the amount of cane cut per minute in the field was significantly correlated with changes in body weight (r = +0-53) during the third hour of work, aerobic energy expenditure (r = + 0-43), and cardiac frequency during work. These variables in turn were associated with predicted maximal power output (VO2 max) measured in the laboratory. The average energy expenditure during cane cutting was 1-66 +/- 0-33 1/min-1 (34-9 kJ/min-1) which represents approximately 60% of the workers predicted VO2 max. This rate of energy expenditure was sustained in the cane fields for at least three hours without significant pauses for rest. The sweat losses measured in 32 cane cutters during the two and three hours of work averaged 637 +/- 221 and 770 +/- 282 g/h-1 respectively, while the mean urine temperature immediately on cessation of effort was 37-74 +/- 0-46 degrees C. Despite the additional environmental heat load of the tropics, it would seem that cane cutters performing a self-paced task demanding heavy physical effort, are able to sustain work levels well in excess of those recommended for most European factory workers without obvious signs of fatigue or heat stress.

Physiological performance and work capacity of Sudanese cane cutters with Schistosoma mansoni infection

Physiological tests of work performance and measurement of field productivity were made in 194 Sudanese cane cutters in order to study the effect of Schistosoma mansoni infection. The cane cutters were selected from two age ranges (16-24 and 25-45 years) and subdivided into three clinical groups: not infected, infected with, and infected without clinical signs of hepatosplenomegaly. Men infected with Schistosoma haemotobium, malaria (blood film), or with hemoglobin levels less than 10 g/100 ml were excluded. There was a statistically significant (P less than 0.002) higher mean hemoglobin concentration in those not infected but the mean difference was less than 1 g/100 ml. Submaximal responses to exercise on a stationary bicycle ergometer, oxygen intake, ventilation, tidal volume, cardiac frequency and estimated maximal aerobic power output calculated both in absolute terms and relative to lean body mass and leg volume were similar in the six groups of cane cutters. No significant differences were found in physique, body composition or in thermoregulatory function tests. The cane cutters were found to have little natural acclimatization to heat in terms of sweating capacity when compared with a group of fully acclimatized Sudanese soldiers. The mean productivity (mean daily weight of cane cut per man) was significantly correlated with the individual's estimated maximum aerobic capacity determined in the laboratory, but not with the degree of S. mansoni infection. The noninfected group was less "efficient" (mean productivity:oxygen intake) during cutting than the infected groups but a larger proportion of the noninfected were in their first season of cutting. There was a positive correlation between the number of seasons' cutting experience and the individual's age, degree of infection and mean productivity. Cane cutters studied in this investigation were a relatively fit, active population from whom the more seriously ill were excluded. These results do not, therefore necessarily reflect the effects of S. mansoni on physiological work capacity and productivity of more static populations in areas of high endemicity.

Comparison of the Bell technique, a modified Kato thick smear technique, and a digestion method for the field diagnosis of schistosomiasis mansoni

A modification of the Kato thick smear technique, the Bell filtration technique, and a digestion method were investigated to determine the relative merits of each for the detection of schistosome eggs in human faecal samples. The modified Kato technique was the method of choice because it was sensitive, simple to perform, and suitable for field use. The Bell filtration technique was equally sensitive in detecting light infections, but was more tedious and more complicated to perform than the thick smear technique.

A simple thick-smear technique for the diagnosis of Schistosoma mansoni infection

A smear technique is described in which thick glass coverslips are substituted for cellulose acetate film soaked in glycerine as used in the Kato technique for stool examination. Estimates of the sensitivity and applicability of this technique for Schistosoma mansoni infections indicate that it compares favourably with the Kato technique, especially for field use.

A large-scale snail control trial with trifenmorph in the Gezira irrigation scheme, Sudan

A large-scale field trial was carried out during December 1973 to assess the effect of trifenmorph on Bulinus truncatus and Biomphalaria pfeifferi in 379 000 feddans ( approximately 159 000 ha) of the Gezira irrigation system in the Sudan. The commercial formulation used (Frescon) is an emulsifiable concentrate containing 16.5% trifenmorph. Five dispensers were used to add the commercial product to the water continuously for 7.5 days; 18 121 litres were used to treat 28.4 million m(3) of water. In addition, each minor canal was hand-sprayed from the tail to 300 m upstream of the last open field outlet pipe; 360 litres of the commercial formulation were used for this operation.A minimum concentration of 0.035 mg trifenmorph per litre of water was produced at the head of each minor canal. The use of caged snails showed that a concentration as low as 0.015 mg/litre was sufficient to produce 100% mortality in B. truncatus in 7.5 days; this is equivalent to a concentration x time product of 0.12 mg/litre days.

Aerial application of N-trityl morpholine to irrigation canals in Sudan

Using a crop-spraying aircraft modified to give a coarse spray, the feasibility of aerial application of the molluscicide N-trityl morpholine to minor canals on the Gezira has been proved. In January 1973, seven canals were sprayed at dosages of 0-1 p.p.m., 0-2 p.p.m., 0-5 p.p.m. and 1-0 p.p.m. Chemical analysis indicated that about 70% of the chemical was present in the water 5-15 hours after the spray, and snail exposure to the sprayed canals indicated that all dosages applied were lethal to Biomphalaria snails. Bulinus snails, which are less susceptible to the molluscicide, were killed only by the 0-5 p.p.m. and 1-0 p.p.m. dosages. Sampling of the natural snail populations of the canals confirmed these results. In March 1973, an area of 464 sq km was treated by drip-feed of 0-1 p.p.m. N-trityl morpholine to kill snails in the main and major canals, and then by aerial spraying 56 of the 58 minor canals in the area. Despite the high winds which disrupted the spray timetable, the canals were successfully treated in 9-5 hours flying-time within seven days. A very high initial snail kill was indicated by both caged snail exposure and natural snail population sampling. However, in excellent snail breeding conditions the area was reinfested with snails within two months. The cost of the application was only 5% of the chemical cost, and aerial spraying in March and May will almost certainly be incorporated in an annual snail control programme.