Dorsal cochlear nucleus responses to somatosensory stimulation are enhanced after noise-induced hearing loss

Multisensory neurons in the dorsal cochlear nucleus (DCN) achieve their bimodal response properties [Shore (2005) Eur. J. Neurosci., 21, 3334-3348] by integrating auditory input via VIIIth nerve fibers with somatosensory input via the axons of cochlear nucleus granule cells [Shore et al. (2000) J. Comp. Neurol., 419, 271-285; Zhou & Shore (2004)J. Neurosci. Res., 78, 901-907]. A unique feature of multisensory neurons is their propensity for receiving cross-modal compensation following sensory deprivation. Thus, we investigated the possibility that reduction of VIIIth nerve input to the cochlear nucleus results in trigeminal system compensation for the loss of auditory inputs. Responses of DCN neurons to trigeminal and bimodal (trigeminal plus acoustic) stimulation were compared in normal and noise-damaged guinea pigs. The guinea pigs with noise-induced hearing loss had significantly lower thresholds, shorter latencies and durations, and increased amplitudes of response to trigeminal stimulation than normal animals. Noise-damaged animals also showed a greater proportion of inhibitory and a smaller proportion of excitatory responses compared with normal. The number of cells exhibiting bimodal integration, as well as the degree of integration, was enhanced after noise damage. In accordance with the greater proportion of inhibitory responses, bimodal integration was entirely suppressive in the noise-damaged animals with no indication of the bimodal enhancement observed in a sub-set of normal DCN neurons. These results suggest that projections from the trigeminal system to the cochlear nucleus are increased and/or redistributed after hearing loss. Furthermore, the finding that only neurons activated by trigeminal stimulation showed increased spontaneous rates after cochlear damage suggests that somatosensory neurons may play a role in the pathogenesis of tinnitus.

Extensive venous/lymphatic malformations causing life-threatening haematological complications

BACKGROUND

Large venous/lymphatic slow-flow malformations (SFM) can be associated with a coagulopathy resulting in thrombosis and haemorrhage. Such potentially life-threatening complications of SFM have been reported only rarely.

OBJECTIVES

To better define the clinical characteristics of haematological complications associated with SFM, to highlight the importance of recognition and to discuss the management of these difficult-to-treat patients.

PATIENTS AND METHODS

A cohort of six children who presented with massive SFM associated with serious haematological complications was seen between January 1980 and June 2005 in the Department of Paediatric Dermatology, Great Ormond Street Hospital for Children, London, U.K. (tertiary referral centre for vascular anomalies). Clinical and haematological characteristics were recorded.

RESULTS

Patients were aged 1-20 years. All suffered with recurrent episodes of pain, localized skin necrosis and bleeding. All had intravascular coagulopathy and life-threatening complications. These included brain haemorrhage, massive bleeding from the uterus and colon, large and extensive thromboses of the deep vessels in the abdomen and pelvis and severe haemoptysis. One patient died suddenly at the age of 20 years from pulmonary thromboembolism and thrombosis within the deep vessels of the vascular malformation. The youngest patient underwent a leg amputation to remove the huge vascular malformation due to the major risk of complications and lack of limb function. Three of the patients underwent anticoagulation treatment and showed improvement in their coagulopathy.

CONCLUSIONS

It is essential that patients with extensive SFM have their coagulation screened regularly to detect intravascular coagulopathy. This may progress to disseminated vascular coagulopathy and a serious risk of thrombosis and haemorrhage. Such patients require early anticoagulation in an attempt to prevent these secondary complications.

Four common glomulin mutations cause two thirds of glomuvenous malformations ("familial glomangiomas"): evidence for a founder effect

BACKGROUND

Glomuvenous malformation (GVM) ("familial glomangioma") is a localised cutaneous vascular lesion histologically characterised by abnormal smooth muscle-like "glomus cells" in the walls of distended endothelium lined channels. Inheritable GVM has been linked to chromosome 1p21-22 and is caused by truncating mutations in glomulin. A double hit mutation was identified in one lesion. This finding suggests that GVM results from complete localised loss of function and explains the paradominant mode of inheritance.

OBJECTIVE

To report on the identification of a mutation in glomulin in 23 additional families with GVM.

RESULTS

Three mutations are new; the others have been described previously. Among the 17 different inherited mutations in glomulin known up to now in 43 families, the 157delAAGAA mutation is the most common and was present in 21 families (48.8%). Mutation 108C-->A was found in five families (11.8%), and the mutations 554delA+556delCCT and 1179delCAA were present together in two families (4.7% each). Polymorphic markers suggested a founder effect for all four mutations.

CONCLUSIONS

Screening for these mutations should lead to a genetic diagnosis in about 70% of patients with inherited GVM. So far, a mutation in glomulin has been found in all GVM families tested, thus demonstrating locus homogeneity.

Sternal malformation/vascular dysplasia syndrome with linear hypopigmentation

We report a 7-year-old boy who presented with a facial haemangioma, a circumscribed depression over the sternum, coarctation of the aorta, ventricular septal defect and dysplastic cerebral arteries responsible for an episode of acute infarct. This combination of clinical features has been described as the sternal malformation/vascular dysplasia syndrome or PHACES syndrome. At the age of 5 years, lines of hypopigmentation were noted on the right arm, the right hand and the back, along the lines of Blaschko, with no history of any preceding inflammatory changes, and have persisted unchanged. These pigmentary changes have not previously been reported in association with this syndrome.

Outcome of antenatally suspected congenital cystic adenomatoid malformation of the lung: 10 years' experience 1991-2001

OBJECTIVE

To determine the outcome of antenatally suspected congenital cystic adenomatoid malformation of the lung (CCAM) over a 10 year period.

METHODS

This is a retrospective study of all babies diagnosed antenatally in the Prenatal Diagnosis Unit and delivered in Oxford between 1991 and 2001. Data were obtained from the Oxford Congenital Anomaly Register, theatre records, and histopathology reports.

RESULTS

Twenty eight cases of CCAM were diagnosed antenatally. Five pregnancies were terminated. Data are available on all 23 of the pregnancies that continued and resulted in two neonatal deaths and 21 surviving babies. Eleven of the 23 cases (48%) showed some regression of the lesion antenatally, and four of these cases appeared to resolve completely on prenatal ultrasound. Three of the 23 babies (13%) were symptomatic in the early neonatal period, and three developed symptoms shortly afterwards. Seventeen of the 23 babies (74%) were asymptomatic, of whom 12 had abnormalities on chest radiograph or computed tomography scan and had elective surgery. Two babies (8%) had completely normal postnatal imaging, and three had abnormalities which resolved in the first year of life. Seventeen of the 23 babies (74%) had surgery. Histology at surgery was heterogeneous. Of the 23 live births, all 21 survivors (91%) are well at follow up or have been discharged.

CONCLUSIONS

All babies diagnosed antenatally with CCAM require postnatal imaging with computed tomography irrespective of signs of antenatal resolution. In asymptomatic infants, the recommendations are close follow up and elective surgery for persistent lesions within the first year of life. Histology at surgery was heterogeneous, and this should be considered when counselling parents.

A systemic route for drug loading to lymphatic phagocytes

Lymph nodes are primary germination and proliferation sites for many types of pathogens. Maintaining therapeutic levels of appropriate chemotherapeutic agents in the lymph node tissue is critical for the treatment of both infection and cancer. This study was intended to develop a systemic route for loading lymph node phagocytes with drugs, using a lymph node specific nanocarrier. The latter is assembled as a 10-15 nm particle with a drug-carrying core and a phagocyte-homing poly(1-->6)-alpha-d-glucose based interface. Biokinetics and microdistribution of the model carrier were investigated in vivo. Nanocarrier accumulation in lymph nodes reached 30-35% dose/g in central lymph nodes, with deposition in various phagocytic cell populations. The latter included cells harboring inhaled microparticles translocated to lymph nodes from the lungs. In view of the nanocarrier ability to transport and release significant amounts of various drug substances, the data suggests feasibility of systemic drug loading to lymphatic phagocytes and, through drug release, to the neighboring cells.

Obstetric fistula: the challenge to human rights

Obstetric fistula can be explained to result from different causes. These holes in the tissue wall between the vagina and bladder and/or rectum are most prevalent in resource-poor countries, attributable to prolonged obstructed labour and absent or inaccessible remedial prenatal services. Obstructed labour is often due to small pelvic size, resulting from women's youth and premature childbearing and/or malnutrition. Poverty at national health-service and family levels often predisposes pregnant populations to suffer high rates of fistula. Global estimates showing up to 100,000 new cases each year and 2 million affected girls and women are probably gross underestimates. Fistula devastates lives of sufferers, who are often expelled by husbands and become isolated from their families and communities. Failures of states to provide prenatal preventive care (including medically indicated cesarean deliveries) and timely fistula repair violate women's internationally recognized human rights, especially to healthcare in general and reproductive healthcare in particular.

Synthesis of a Macromolecular Camptothecin Conjugate with Dual Phase Drug Release

A water soluble macromolecular conjugate of camptothecin (CPT) with a new, dual phase hydrolytic drug release mechanism was prepared on the basis of a 60 kDa biodegradable hydrophilic "stealth" polyacetal, poly(1-hydroxymethylethylene hydroxy-methyl formal). Succinamido-glycinate was used as a prodrug releasing group. A model preparation with 7.5% CPT content w/w was water soluble. The lipophilic camptothecin prodrug, camptothecin-(O20)-succinimidoglycinate, was released from the conjugate with t(1/2) = 2.2 +/- 0.1 h in rodent plasma. The blood clearance in a rodent model as measured by CPT was release limited, t(1/2) = 2.1 +/- 0.2 h, while the conjugate half-life was 14.2 +/- 1.7 h. In a xenograft tumor model, the conjugate demonstrated higher antineoplastic efficacy than CPT at a less than equitoxic dose. This improved therapeutic window is in line with the modified drug pharmacokinetics and with camptothecin release in a stabilized lipophilic prodrug form. Regulation of prodrug release and hydrolysis rates through linker structure modification will open the way to further improve both pharmacokinetics and pharmacodynamics.

Cutaneous haemangioma: prevalence and sonographic characteristics of associated hepatic haemangioma

AIMS

To determine the prevalence of hepatic haemangiomas (HH) occurring with multiple or large cutaneous haemangiomas (CH), and compare the ultrasound (US) characteristics of HH with morphology of concurrent CH.

MATERIALS AND METHODS

Retrospective and prospective sonographic and clinical analysis was undertaken on 69 patients referred for US to exclude silent HH. This comprised 62 patients referred over 6 years with six or more CH or one large CH (#10878;5 cm) and seven patients referred over 1 year with three to five small CH.

RESULTS

HH occurred in 45% miliary CH and 40% mixed small and large CH, but also in 12-14% of patients with one large or three or more small CH. None had HH progression. There was association between HH sonographic characteristics and CH number and morphology.

CONCLUSION

Clinically silent HH occurred in nearly one in four of infants presenting overall with six or more small CH or large CH. Previous studies have documented HH mortality between 18 and 80%, although this was not shown in our study. Therefore, if clinical suspicion exists, US is indicated to enable early steroid treatment if significant HH are present.

Hormone replacement therapy menopause with a better future--a survey of views on hormone replacement therapy (HRT)

OBJECTIVE

To assess the views and prescribing practices of doctors regarding hormone replacement therapy (HRT).

METHODS

In April 1999, 103 doctors from a teaching hospital participated in a survey. Using a self-administered questionnaire, subjects were contacted at the departments of Internal Medicine, Family Medicine, Obstetrics and Gynaecology, and Orthopaedics.

RESULTS

Seventy-two percent were below 40 years of age and 67% of the respondents were male. Most doctors believed that HRT decreases the risk of subsequent osteoporosis (97%), ischaemic heart disease (77%) and depression associated with menopause (64%). Doctors generally considered menopausal symptoms (90%), premature menopause (87%), surgical menopause (85%) and osteoporotic fracture (77%) as clear indications for hormone replacement therapy. Absolute contraindications to the therapy were stated as recent breast cancer (82%) and recent endometrial cancer (84%). Among the specialities covered, there were differing views on proposed duration of HRT. It was generally believed that a pelvic examination, cervical smear and mammography were pre-requisites when initiating and monitoring HRT. Majority (69%) felt that HRT should be offered to all menopausal women, assuming no contraindications and most (73%) did discuss HRT with their patients. However, less than 10% of the menopausal patients under their care were using HRT. Those doctors not in favor of universal offering of HRT (31%) considered unreliable patient follow up to be the main reason. Females were two times more likely to discuss HRT with their patients (p = .08). Doctors who discussed HRT with their patients were four times more likely to consider HRT for themselves or their spouses (p = .13). Gynecologists were eight times more likely to prescribe HRT than non-gynecologists (p = .001).

CONCLUSION

Doctors are positively disposed to the universal offering, and use of HRT. Further studies are needed to understand a possible gap between perceived and actual prescribing practice.

Thoracic splenosis diagnosed by fine-needle aspiration cytology: a case report

A case of thoracic splenosis diagnosed by fine-needle aspiration (FNA) of subpleural lung lesions is presented. The patient, a 49-yr-old male with a history of gunshot wound to his trunk with splenic rupture and splenectomy several years previously, presented with recent hemoptysis and multiple subpleural solid nodules shown in the left lung field by CT scan. As the possibility of a metastatic malignancy vs. mesothelioma was entertained, an FNA was performed on one of these lesions, revealing lymphoid tissue with abundant vascularity simulating the structure of splenic tissue. In view of this finding, supported by the absence of splenic outline in the CT radiograph, the diagnosis of splenosis was made. This is the fourth reported case of thoracic splenosis in which FNA cytology was utilized for diagnosis, yet the first in which the diagnosis was based exclusively on the FNA cytologic findings. Clinical, pathologic, and diagnostic aspects of this entity are discussed.

Prolonged in vivo anticoagulant activity of a hirudin-albumin fusion protein secreted from Pichia pastoris

Hirudin is a small, proteinaceous thrombin inhibitor that clears rapidly from the circulation. A hexahistidine-tagged hirudin-rabbit serum albumin (RSA) fusion protein, HLAH6, was characterized following secretion from Pichia pastoris. HLAH6 bound to immobilized nickel, anti-RSA, and anti-hexahistidine antibodies, and contained the expected (ITYTD) N-terminus. Its spectrometric mass was 74,490 (versus the theoretical mass of 74,410 and sodium dodecyl sulfate-polyacrylamide gel electrophoresis mobility of 84 kDa). The terminal catabolic half-life in rabbits of HLAH6, recombinant Pichia-derived His-tagged RSA, or plasma-derived RSA did not differ. Injection of 2 mg/kg HLAH6 into rabbits raised the activated partial thromboplastin time (aPTT) above initial values for 4-24 h, while the equimolar dose of unfused hirudin was without significant effect. A higher dose of HLAH6 (3 mg/kg functional HLAH6, equivalent to 37.6 thrombin-inhibitory units/g) raised the aPTT by 2.0- to 2.5-fold; the elevation persisted for > 48 h. Importantly, both HLAH6 and unfused hirudin inhibited clot-bound thrombin. Our results suggest that HLAH6 exhibits not only delayed clearance, but also prolonged biological activity in vivo compared with unfused hirudin.

Behind the counter: pharmacies and dispensing patterns of pharmacy attendants in Karachi

BACKGROUND

There is little literature available on dispensing patterns and unsupervised sale of medicines from pharmacies in developing countries.

OBJECTIVE

This study obtained background information on pharmacies, assessed the level of training, knowledge and dispensing patterns of pharmacy attendants in Karachi.

METHODOLOGY

This is a descriptive cross sectional study with convenient sampling. A structured questionnaire was used to interview pharmacy attendants.

RESULTS

Of the 219 pharmacies surveyed, 62% reported more than 50 customers daily and 20% also sold items of general provision. Mean operating hours were 13. Only 24 (11%) had a visible license. On an average 3 attendants were employed per pharmacy. We interviewed one in each. Amongst the 219 interviewed, 77 (35%) were intermediate qualified and only 26 (12%) pharmacologically trained. Correct frequency of ORS administration was not known by 167 (76%) and 21% incorrectly suggested an anti-diarrhoeal preparation for viral diarrhoea in children. The knowledge of those with pharmacological training was significantly better. For respiratory tract infection in children approximately 60% did not know the correct dose of Paracetamol and Amoxicillin. Only 13 (6%) knew that Propanalol was contraindicated in hypertensive asthamatics. For Cotrimoxazole, metronidazole and lomotil only 40%, 21% and 15% respectively, were aware that these could not be dispensed without prescription.

CONCLUSION

In the absence of trained pharmacists existing pharmacy attendants should be trained to improve drug-dispensing patterns.

Comparison of molecular changes in cervical intraepithelial neoplasia in HIV-positive and HIV-indeterminate subjects

OBJECTIVE

HIV infection is associated with an increased incidence of cervical malignancy and its precursor lesions (CIN, cervical intraepithelial neoplasia) compared with the general population. We studied the molecular abnormalities in the development of HIV-associated CIN and compared them with those present in CINs arising in HIV-indeterminate subjects ("sporadic CIN").

METHODS

We investigated the presence of human papilloma virus (HPV) sequences, loss of heterozygosity (LOH), and microsatellite alterations (MAs) at five 3p chromosomal regions using 17 polymorphic markers in precisely microdissected archival tissues from 16 HIV-positive CINs and compared them with those present in 39 sporadic CINs.

RESULTS

HPV sequences were detected in 36 of 55 (66%) CIN lesions, and high-risk oncogenic strains (HPV 16 and 18) accounted for 15 of them. No differences in the HPV frequencies were found between HIV-associated and sporadic CINs. Allelic losses at one or more chromosome 3p regions were frequently detected in CIN lesions (49%). The overall frequency of 3p LOH and the frequencies at all individual regions were similar in HIV-associated and sporadic CINs. The frequency of MA present in the HIV-associated CIN cases (0.093) was sixfold greater than in sporadic CINs (0.014; P = 0.0001). At least 1 MA was present in 11 (69%) of 16 HIV-associated vs. 5 of 39 (13%) sporadic CIN (P = 0.0006). Molecular changes were independent of the presence of HPV sequences.

CONCLUSION

Chromosome 3p deletions are frequently detected in the precursor lesions of cervical carcinoma (CIN) and there are no differences in the 3p LOH frequencies between HIV-associated and sporadic CIN lesions. Microsatellite alterations, which reflect widespread genomic instability, occur at greatly increased frequency in HIV-associated CIN. Although the mechanism underlying the development of increased MAs is unknown, it may play a crucial role in the development of many HIV-associated neoplasias.

Allelic losses at chromosome 8p21-23 are early and frequent events in the pathogenesis of lung cancer

Allelic losses on the short arm of chromosome 8 (8p) have been reported as frequent events in several cancers, including lung. However, no comprehensive mapping analysis of chromosome 8p in lung cancer tumors has been performed, and no data are available about the stage at which these abnormalities occur during the multistage development of lung cancer. Using 26 microsatellite markers, we mapped the chromosome 8 regions frequently deleted in lung cancer in 13 small cell carcinoma and 17 non-small cell lung carcinoma cell lines and in 68 microdissected archival primary lung tumors (22 small cell lung carcinomas, 25 squamous cell carcinomas, and 21 adenocarcinomas). We also studied the role of 8p deletions in lung cancer pathogenesis by examining 95 microdissected normal epithelium and preneoplastic samples from 11 surgically resected squamous cell lung carcinomas and from 58 bronchoscopy biopsy samples obtained from 31 current and former smokers. High frequencies of deletions at 8p21-23 regions were detected in lung cancer cell lines and in primary lung tumors. Deletions commenced early during the multistage development of lung cancer at the hyperplasia/metaplasia stage in cancer patients and in smokers without cancer. Allelic deletions persisted for up to 48 years after smoking cessation. There was a progressive increase of the overall 8p21-23 loss of heterozygosity frequency and in the size of the deleted region with increasing severity of histopathological preneoplastic changes. In epithelial samples from resected squamous cell lung carcinomas, we compared the presence of loss of heterozygosity at 8p21-23 with deletions at chromosomes 3p and 9p. Of interest, the pattern of deletions was not random, and 8p21-23 allelic losses always followed 3p deletions and usually followed 9p deletions. We conclude that 8p21-23 deletions are frequent and early events in the pathogenesis of lung carcinomas.

Psoralen photobiology and photochemotherapy: 50 years of science and medicine

In 1998 it is appropriate to commemorate the 50th anniversary of el Mofty's use of purified 8-methoxypsoralen (8-MOP) in the treatment of vitiligo (el Mofty AM. A preliminary clinical report on the treatment of leukoderma with Ammi majus linn. J R Egypt Med Assn 1948,31:651 65. el Mofty AM, el Sawalhy H, el Mofty M. Clinical study of a new preparation of 8-methoxypsoralen in photochemotherapy. Int J Dermatol 1994;8:588 92). Two young American dermatologists (Aaron Lerner and Thomas Fitzpatrick) were intrigued by the potency of this material. After Lerner determined that artificial long wavelength ultraviolet (320-400 nm, UVA) radiation was the most efficient for activating 8-MOP. the development of artificial sources enabled the efficient delivery of these photons to skin containing 8-MOP. Their initial studies for vitiligo led to further development of this therapy for the treatment of psoriasis (Parrish JA, Fitzpatrick TB, Tannenbaum L, et al. Photochemotherapy of psoriasis with oral methoxsalen and long-wave ultraviolet light. New Engl J Med 1974;291:1207-11. Honigsmann H, Fitzpatrick TB, Pathak MA, et al. Oral photochemotherapy with psoralen and UVA (PUVA): principles and practice. In: Fitzpatrick TB, Eisen AZ, Wolf K, editors. Dermatology in General Medicine. New York: McGraw-Hill, 1987:1728-54). This photochemotherapy came to be called 'PUVA' (psoralen + UVA). The position PUVA holds today as one of the most common procedures performed in dermatology can be traced to their initial curiosity and their subsequent ingenuity. Further developments in more recent years capitalized on their seminal work. The therapy met with unprecedented success from the outset, leaving little perceived need to understand underlying science. However, in recent years there has been a new found interest in the basic aspects of psoralen photobiology and molecular mechanistic events contributing to therapeutic responses as well as to the development of skin cancers in PUVA patients. These will be surveyed in this review commemorating the 50 years of modern psoralen photobiology and photomedicine.

Comparison of features of human breast cancer cell lines and their corresponding tumors

Although human tumor-derived cell lines play an important role in the investigation of cancer biology and genetics, there is no comprehensive study comparing tumor cell line properties with those of the individual tumors from which they were derived. We compared the properties of a series of 18 human breast cancer cell lines that were cultured for a median period of 25 months (range, 9-60 months) and their corresponding archival tumor tissues. We compared morphological characteristics, ploidy, and immunohistochemical expression of estrogen receptors, progesterone receptors, and HER2/neu and p53 proteins. For 17 of these cases, we also tested for allelic losses at 18 chromosomal regions frequently deleted in breast tumors using 51 polymorphic microsatellite markers, and we determined the TP53 gene mutation status in exons 5 to 10. There was an excellent correlation between the breast tumor cell lines and their corresponding tumor tissues for morphological features (100%); presence of aneuploidy (87%); immunohistochemical expression of estrogen receptors (87%), progesterone receptors (73%), and HER2/neu (93%) and p53 proteins (100%); allelic loss at all of the chromosomal regions analyzed (82-100% concordance); and TP53 gene mutations (75%). The same parental allele was lost in 279 (99%) of 281 of the comparisons of allelic losses. The fractional allelic loss indices (a reflection of the total allelic loss) of the cell lines and their corresponding tumor tissues were identical or similar in 15 (88%) of 17 paired comparisons. Although our previous studies (A. Gazdar et al., Int. J. Cancer, in press) indicated that only a subset of primary breast carcinomas that have several features indicative of advanced tumors with poor prognosis can be successfully cultured, the cell lines retain the properties of their parental tumors for lengthy culture periods and, thus, provide suitable model systems for biomedical studies.

Effect of subcutaneous injection of granulocyte-macrophage colony stimulating factor (GM-CSF) on healing of chronic refractory wounds

OBJECTIVE

To assess the effect of granulocyte macrophage colony-stimulating factor (GM-CSF) on healing of chronic wounds.

DESIGN

Prospective open study.

SETTING

1 cancer hospital and 2 University hospitals, Pakistan.

SUBJECTS

35 patients with chronic wounds (duration 3 months or longer) that had not responded to standard treatment. Patients with malignant ulcers were excluded.

INTERVENTION

GM-CSF 10 microg/cm2 was injected subcutaneously along the edges and base of the wound. The treatment was given only once and patients were followed weekly for a minimum of six weeks.

MAIN OUTCOME MEASURES

Changes in size, shape, depth, edges and base of the wound, amount and quality of the granulation tissue, and type of discharge.

RESULTS

Six patients were excluded from the analysis, 4 who died early of underlying disease and were not evaluable, and 2 who were excluded when histological examination of the wound showed that it was malignant. Although various types of wounds were studied, most (n = 10, 34%) were postoperative. 23 of the wounds were over 2 cm in diameter (mean 4.8 x 4.6 cm) with thin granulation tissue, and almost half were infected. Nine of the 29 wounds healed completely within six weeks while another 11 decreased in size by more than 50%; 7 patients responded slightly. Only two wounds showed no evidence of healing during the observation period. More than half of the 20 wounds that responded had healed by three weeks. Response did not correlate with any clinical variable including the presence of infection. Toxicity was negligible.

CONCLUSIONS

We conclude that subcutaneous injection of a single dose of GM-CSF may induce healing in refractory chronic wounds. Trials are necessary to validate these initial observations and to decide the optimal dose and route, and whether any additional benefit may be derived from repeated injections.

Sensitivity pattern and beta-lactamase production in clinical isolates of Aeromonas strains

Of the 43 Aeromonas spp. isolated from various clinical samples 94% isolates were Beta-lactamase producers. The isolates were tested for sensitivity by disc diffusion method which is commonly used in Pakistan. MIC was determined by using Epsilometer test (E-test) method. More than 80% isolates were sensitive to cephalosporins and quinolones. However, resistance to commonly used antibiotics was very high, 94% isolates were resistant to ampicillin which corresponds to the betalactamase production. More than 60% of the isolates were resistant to cotrimoxazole and 40% to chloramphenicol, hence quinolones and cephalosporins appear to be the drugs of choice for treating serious Aeromonas infections. The MIC range of Aeromonas was best for cefotaxime < 0.06 - 1.0 ug/ml. MIC 90 for cefotaxime was 0.50 ug/ml, for imipenem 0.25 ug/ml and for ciprofloxacin 2.0 ug/ml.

The effect of an absorbable collagen membrane on the subgingival microflora

The purpose of this study was to determine the effect of use of an absorbable collagen membrane in guided tissue regeneration (GTR) therapy upon the subgingival microflora. The study group consisted of 12 systemically healthy patients with bilateral mandibular furcation defects with attachment loss > or = 6 mm; one site was randomly assigned for GTR treatment while the contralateral site received surgical flap debridement only. Subgingival plaque samples were collected by paper point on the day of surgery and at 2, 4 and 6 months post-surgery. Three sites were sampled in each patient: a collagen membrane site, a control surgical site, and an unoperated control site. Plaque samples were transported in a non-phosphated buffer solution and examined by phase-contrast microscopy. Cocci, rods, spirochetes, fusiforms, curved rods, and total bacteria were recorded per 10 high-power fields. Following statistical analysis utilizing the Bonferroni (Dunn) t test, no differences in total bacterial counts were found among the sites at any of the time intervals examined. Total bacterial counts were found lower at both the collagen membrane and control surgical sites post-surgery as compared to unoperated control sites, but these differences were not statistically significant (P > .05). In addition, no significant differences were detected in bacterial profiles between sites or individual time points. Results from this 6-month limited clinical trial suggest that the placement of an absorbable collagen membrane as part of a standard surgical regimen for GTR therapy does not alter the local microflora.

Predictive value of MCV/RBC count ratio to discriminate between iron deficiency anaemia and beta thalassaemia trait

AIM AND BACKGROUND

Two forms of hypochromic microcytic anaemia i.e. iron deficiency and beta-thalassaemia trait are common in our society. This study reports the prevalence of iron deficiency anaemia and beta-thalassaemia trait and predictive value of MCV/RBC count ratio to discriminate between two.

METHODS

Venous blood was taken from 299 students of Karachi Medical & Dental College and Ziauddin Medical University in Na2 EDTA and analyzed by semi-automated Sysmex K-1000 haematology analyzer. MCV/RBC count ratio was used to discriminate between iron deficiency and beta-thalassaemia trait and > 14% was marked as iron deficiency. Hb electrophoresis was used as gold standard test for confirmation. Serum iron and TIBC was performed to confirm iron deficiency anaemia.

RESULTS

Iron deficiency was found in 9% while beta-thalassaemia was seen in 3% students. MCV/RBC count ratio showed a positive predictive value of 91%.

CONCLUSIONS

In areas where iron deficiency anaemia and beta-thalassaemia trait are common, MCV/RBC count ratio can be used to screen out beta-thalassaemia trait.

Isolation and identification of Aeromonas species from human stools

One thousand and three diarrhoeal stool samples were processed in our laboratory during the period 1996/1997 for the presence of enteric pathogens especially Aeromonas spp., which has emerged as a new agent causing diarrhoea. Ampicillin sheep blood agar was found to be the best medium for the isolation of Aeromonas spp. from stool specimens. Enteric pathogens were found in 200 (20%) stools, of which Aeromonas spp. was the second commonest pathogen isolated amounting to 21% of isolates. This study clearly indicates that Aeromonas spp. must be looked for in every diarrhoeal stool samples, specially in children below 10 years of age. Isolation and identification is cost effective and easy, if the given protocol is observed.