To Cross or Not to Cross: Using MRI-Histology to Characterize Dense Collagenous Plaque in Critical Limb Ischemia

Peripheral artery disease (PAD) is caused by atherosclerotic buildup in the lower extremities, leading to obstruction and inadequate perfusion to the peripheral vasculature. Impenetrable plaques initially treated with percutaneous vascular intervention (PVI) have led to worse secondary bypass outcomes and amputation in patients. In this case report, we discuss the importance of using magnetic resonance imaging (MRI) histology in PVI planning in a patient with critical limb ischemia. PVI attempts to recanalize the limb failed because of an impenetrable occlusion in the popliteal artery that was not identified on routine preoperative imaging. Subsequent bypass occluded multiple times eventually requiring an above-knee amputation. An MRI-histology protocol-using ultrashort echo time (UTE) and T2-weighted (T2W) sequences-that was performed prior to the index PVI identified the occlusion as a dense collagen plaque. Histology analysis of the amputated specimen confirmed the MRI finding. This imaging modality offers a novel approach to characterize plaque composition and morphology, thereby identifying lesions at greatest risk of PVI failure and potentially playing an important role in selecting the right candidates for an endovascular-first approach.

Low cerebral blood flow is a non-invasive biomarker of neuroinflammation after repetitive mild traumatic brain injury

Previous work has shown that non-invasive optical measurement of low cerebral blood flow (CBF) is an acute biomarker of poor long-term cognitive outcome after repetitive mild traumatic brain injury (rmTBI). Herein, we explore the relationship between acute cerebral blood flow and underlying neuroinflammation. Specifically, because neuroinflammation is a driver of secondary injury after TBI, we hypothesized that both glial activation and inflammatory signaling are associated with acute CBF and, by extension, with long-term cognitive outcome after rmTBI. To test this hypothesis, cortical CBF was non-invasively measured in anesthetized mice 4 h after 3 repetitive closed head injuries spaced once-daily, at which time brains were collected. Right hemispheres were fixed for immunohistochemical staining for glial activation markers Iba1 and GFAP while left hemispheres were used to quantify Iba1 and GFAP expression via Western blot as well as 32 cytokines and 21 phospho-proteins in the MAPK, PI3K/Akt, and NF-κB pathways using a Luminex multiplexed immunoassay. N = 8/7 injured/sham C57/black-6 adult male mice were studied. Within the injured group, CBF inversely correlated with Iba1 expression (R = -0.86, p < .01). Further, partial least squares regression analysis revealed significant correlations between CBF and expression of multiple pro-inflammatory cytokines, including RANTES and IL-17. Finally, within the injured group, phosphorylation of specific signals in the MAPK and NF-κB intracellular signaling pathways (e.g., p38 MAPK and NF-κB) were significantly positively correlated with Iba1. In total, our data indicate that acute cerebral blood flow after rmTBI is a biomarker of underlying neuroinflammatory pathology.

Heme and hemoglobin suppress amyloid β-mediated inflammatory activation of mouse astrocytes

Glial immune activity is a key feature of Alzheimer's disease (AD). Given that the blood factors heme and hemoglobin (Hb) are both elevated in AD tissues and have immunomodulatory roles, here we sought to interrogate their roles in modulating β-amyloid (Aβ)-mediated inflammatory activation of astrocytes. We discovered that heme and Hb suppress immune activity of primary mouse astrocytes by reducing expression of several proinflammatory cytokines (e.g. RANTES (regulated on activation normal T cell expressed and secreted)) and the scavenger receptor CD36 and reducing internalization of Aβ(1-42) by astrocytes. Moreover, we found that certain soluble (>75-kDa) Aβ(1-42) oligomers are primarily responsible for astrocyte activation and that heme or Hb association with these oligomers reverses inflammation. We further found that heme up-regulates phosphoprotein signaling in the phosphoinositide 3-kinase (PI3K)/Akt pathway, which regulates a number of immune functions, including cytokine expression and phagocytosis. The findings in this work suggest that dysregulation of Hb and heme levels in AD brains may contribute to impaired amyloid clearance and that targeting heme homeostasis may reduce amyloid pathogenesis. Altogether, we propose heme as a critical molecular link between amyloid pathology and AD risk factors, such as aging, brain injury, and stroke, which increase Hb and heme levels in the brain.

Medication management in people with Parkinson's disease during surgical admissions

BACKGROUND

Patients with Parkinson's disease (PD) may experience problems in hospital, with their medication being withheld or inappropriate medication being prescribed. Since surgical admissions present particular risks, the authors examined the management of patients with PD on surgical wards.

METHODS

All patients with PD admitted to surgical departments in Aberdeen Royal Infirmary during an 18-month period were identified. Medical and nursing notes were reviewed retrospectively, and drug prescription and administration were studied in detail. All documented complications were recorded.

RESULTS

59 surgical admissions (51 receiving PD medication, median duration 6 days) were studied. 71% had missed doses of PD medication, with 34% missing over 10% of prescribed doses. Values were similar for levodopa and agonists. Overall, 12% of all prescribed PD medication was missed (mean 0.7 missed doses per patient per day). No reason for missed doses was recorded in 64% of cases, while inappropriate reasons included 'out of stock' (12%) and 'nil by mouth' (8%). Centrally acting antidopaminergic drugs (mainly antiemetics) were prescribed in 41% of cases, and administered in 22%. Complications, most commonly neuropsychiatric, were documented in 69% of non-day-case admissions.

CONCLUSION

Poor prescribing and incomplete drug administration are common in patients with PD on surgical wards. Measures to improve management are identified.

Trilateral retinoblastoma. A report of five patients

BACKGROUND

Trilateral retinoblastoma is a well recognized, although rare, syndrome. Most of the reported cases have involved a family history of retinoblastoma (RB) and the disease is almost always fatal. The authors chose to investigate the cases of trilateral retinoblastoma occurring in the West Midlands, a region of the United Kingdom with an increasing incidence of bilateral sporadic RB.

METHODS

Five patients with trilateral retinoblastoma (including two were previously reported), diagnosed in 146 consecutive patients with RB in the West Midlands Health Authority Region between 1957 and 1994, are presented (an incidence of 3%). Their clinical presentation, treatment, and outcome are described.

RESULTS

There were 4 patients with pineoblastoma, only one of whom had a positive family history. The mean age at diagnosis of RB and 6 months, whereas the patients with pineoblastoma were diagnosed at a mean age of 2 years 8 months. The tumors were not evident on the initial computed tomography scans. One child presented with a calcified suprasellar mass 13 months before the bilateral sporadic RB was identified. Death occurred within 1 month of diagnosis of the intracranial tumor in 3 patients who did not receive any treatment. In the other 2 patients who were treated, death occurred at 15 months and 2 years 7 months, respectively, after diagnosis of intracranial tumor.

CONCLUSIONS

Early diagnosis with regular neuro-imaging and more aggressive treatment may improve prognosis in patients with RB and an intracranial tumor.

Carcinoma of the nasopharynx in young patients

PURPOSE

To provide an analysis of eighteen cases of adolescent nasopharyngeal carcinoma treated between 1971 and 1989.

METHODS AND MATERIALS

Between 1971 and 1989, 48 cases of nasopharyngeal carcinoma were evaluated at the Medical College of Georgia Hospital and Clinics. Eighteen patients between the ages of 9 and 29 years were treated at the Georgia Radiation Therapy Center. All patients presented for treatment with (AJCC) Stage IV disease. Fifteen patients with lymphoepithelioma and three with squamous cell carcinoma histologies received definitive radiation therapy to a median dose of 64.8 Gy. Males outnumbered females by more than 2:1 and the majority of patients (67%) were black. Nine patients received multiagent adjuvant chemotherapy.

RESULTS

Thirteen patients are alive from 7 to 166 months (median 32 months) including three with disease at 17, 24, and 132 months. Overall and disease-free survival at 5 and 10 years were 63% and 54%, respectively. Five patients died from disease; four patients had pulmonary metastases while one had CNS metastasis. Eighty percent of relapses occurred within the first 2 years following treatment. Acute and chronic toxicities were limited, consisting primarily of mucositis and xerostomia. Radiation doses of 65 Gy or more (p = 0.049) and age greater than 20 years (p = 0.005) were positive prognosticators for survival. Adjuvant chemotherapy, race, and sex were not found to be of prognostic value. Disparities in the distribution of patients with lymphoepithelioma and squamous cell histologies and the presentation of advanced regional disease precluded analysis for prognostic significance of histology and nodal status in this series.

CONCLUSION

The results of the present series compare favorably with those published from other institutions. High doses of radiation and a high systemic failure rate continue to be the fundamental obstacles to effective management and enhanced survival for patients with nasopharyngeal carcinoma.

Glomerular morphometry in reflux nephropathy: functional and radiological correlations

Using computerized digitometry, we investigated the relationships between renal size, glomerular filtration rate (GFR), proteinuria, incidence of segmental and global glomerulosclerosis, glomerular size, hilar arteriolar wall thickness and hyaline deposition in renal biopsies obtained from 24 children and adolescents with reflux nephropathy, of whom only 4 were hypertensive. Age-matched controls comprised minimal-change nephrotic syndrome (6) and recurrent haematuria with normal biopsy (13). The mean sectional area of patients' glomeruli was double that of controls. Glomerular size correlated with the amount of proteinuria (measured as protein/creatinine ratios in early morning urine) and inversely with renal size and GFR. Segmental sclerosis, invariably of hilar origin, was observed in 8 patients and the percentage of glomeruli affected correlated strongly with glomerular size and proteinuria. Global sclerosis was found equally in patients and controls, and showed no similar correlations. Compared with controls, patients' hilar arterioles showed increased wall thickness, more intramural hyaline deposits and decreased luminal diameter when related to glomerular size. The proteinuria and glomerular changes are consistent with hyperfiltration, while the previously undescribed hilar vascular changes, which both precede and accompany sclerosis, resemble abnormalities reported experimentally following renal ablation.

Cisplatin-based chemotherapy in advanced basal and squamous cell carcinomas of the skin: results in 28 patients including 13 patients receiving multimodality therapy

This study reports the results of cisplatin (CDDP)-based chemotherapy (CT) as sole therapy and as neoadjuvant (NA) therapy in 28 consecutive patients (pts) with advanced basal cell (BC) and squamous cell (SC) cancers of the skin. CT in 24 pts consisted of CDDP 75 mgm/m2 and doxorubicin (Dox) 50 mg/m2 intravenously (IV) every 3 weeks with Dox being omitted in four pts due to severe preexisting cardiac disease. Thirteen of the 28 pts received CT in the NA setting, five before surgery and eight before radiation therapy (RT). Response rates to CT were complete remission (CR) in eight of 28 (28%) pts, partial remission (PR) in 11 of 28 (40%) for an overall response rate of 68%. Thirteen pts received a second treatment modality with five of 13 pts having a CR to CT alone before the second modality and seven converting to CR postsecond modality for a total CR rate of 12 of 13 (92%) in the multimodality group. Duration of responses in the CT-only group ranged from 4 to 82 months; however, only two patients remain in remission in this group. Of the twelve CRs from the multimodality therapy group, 11 of 12 (91%) pts remain in CR with duration of response ranging from 3 to 81 months. Toxicities were manageable, with no toxic deaths and only five pts stopped CT secondary to side effects. This study suggests the combination of CDDP and Dox is highly effective in BC and SC cancers of the skin and by itself can produce long unmaintained remissions, but when combined with a second modality of therapy, it is capable of producing not only long unmaintained CRs but probable cures in the majority of pts.

Computed tomography of Grave's ophthalmopathy. Diagnosis, management, and posttherapeutic evaluation

Computed tomography (CT) is emphasized in the diagnosis and management of Grave's ophthalmopathy. This report illustrates the value of CT in evaluating the extent of disease, choice and timing of treatment, radiation therapy planning, and posttreatment follow-up of nine patients with Grave's ophthalmopathy. Eight patients had bilateral disease, and three patients had evidence of optic nerve compression. Postirradiation follow-up CT was done in three patients. Eight patients treated with radiation obtained good response.

Invasive squamous cell carcinoma of the vagina: a 14-year study

A retrospective review was conducted of patients with squamous cell carcinoma of the vagina managed at one institution over a 14-year period. The 28 cases of squamous cell vaginal carcinoma constituted 3.1% of all female genital tract cancers. Forty-six percent of the patients had undergone a previous hysterectomy for benign disease or for cervical intraepithelial neoplasia; 14.2% had had irradiation. Disease of stage III or greater occurred in 43% of the study group. The majority of patients were treated by radiation therapy. The overall survival was 42.8%. This review indicates that patients who have had a previous hysterectomy should remain under close surveillance.

Ultrasound findings in children with cystic fibrosis

The results of a prospective study using ultrasound to assess abdominal complications in 76 children with proven cystic fibrosis are reported. Fifty-six patients (74%) had normal liver ultrasound scans. The most striking abnormality was an irregular, inferior edge to the liver occurring in 85% of abnormal liver scans and in 70% there was corresponding clinical and biochemical evidence of abnormal liver function. This finding has been only briefly mentioned before. Increased reflectivity in abnormalities of the pancreas and gallbladder is also described.

Adreno-cortical carcinoma in infancy and childhood: a radiological report of ten cases

Adreno-cortical carcinoma is a relatively rare neoplasm in infancy and childhood. This review, covering a period of 18 years (1965-83), revealed 10 cases, the study being prompted by three patients in whom the final diagnosis was considerably delayed. There were eight females and two males and their ages ranged from 6 months to 14 years; 50% were below the age of 18 months at the time of the presentation. Seven patients had features of either virilism or precocious puberty and three of these also had stigmas of Cushing's syndrome. In patients where the endocrine disturbance was evident, the clinical diagnosis was made rapidly. However, delay in diagnosis occurred when endocrinopathy was absent. Radiology, including newer methods of imaging, contributed by revealing the tumour and its spread but did not suggest a conclusive diagnosis. At times, clinical features, biochemical findings, radiological investigations and even histological studies mislead, thus delaying the final diagnosis. These cases are illustrated and discussed.

Beckwith-Wiedemann syndrome: role of ultrasound in its management

There is a well-recognised association between Beckwith-Wiedemann syndrome (BWS), hemi-hypertrophy of a limb and childhood malignancies. Ten children with BWS were seen over a period of 14 years. Their ages ranged from newborn to 14 years and the maximum follow-up extended to 14 years. Three children also had hemi-hypertrophy of the lower limb. In one child Wilms' tumour was diagnosed at the age of 4 years; she was successfully treated with surgery and chemotherapy and has been disease-free for the past 7 years. One patient died in infancy, while the remaining nine children were regularly followed up, including 3-monthly ultrasound scans of the kidneys and upper abdomen. Ultrasonic features of nephromegaly, lobulated margin, corticomedullary cysts and nodules of mixed echogeneity and pelvi-calyceal distension are illustrated. Ultrasound is a non-invasive, non-ionising and safe modality with very little discomfort to the patient and is ideal for regular and frequent follow-up of infants and children with conditions predisposed to malignancy.

Orbital tuberculosis in childhood

An 11-year-old Indian girl living in England developed proptosis due to tuberculosis of the orbit. The proptosis regressed and she recovered fully after chemotherapy. While malignancy, developmental anomalies, and nontuberculous infections are commoner causes, a tuberculin test should be included among the investigations of children with proptosis.

Unusual sites of acute osteomyelitis in childhood

In children osteomyelitis is common in the long hours of femur, tibia and humerus. This study reports 16 children, aged 2-13 years, with osteomyelitis at unusual sites: in the bones of the thoracic cage including three involving the clavicle; in the spine, foot and elsewhere. In one case, multifocal involvement of the vertebral body and the knee occurred. In two large series reported previously, the incidence of osteomyelitis was 1-3% in the clavicle, 3-8% in the calcaneus and less than 1% in the ribs. Four out of 16 cases (two involving clavicles, one rib and one with multifocal sites of the lesion) required open biopsies and histological examination to achieve the final diagnosis of osteomyelitis; in three of these patients the causative agent was not identified on culture. Staphylococcus aureus was the infective organism in 50% of cases where cultures were obtained. In five cases there was no growth on culture and specific search for less common organisms, including mycobacteria tuberculosis (AAFB), proved negative. It is suggested that in such situations diagnostic problems may present as the clinical and radiological findings may not be specific or conclusive. In such cases early biopsy is mandatory.

4-hydroxyquinoline-3-carboxylic acids as inhibitors of cell respiration. 2. Quantitative structure-activity relationship of dehydrogenase enzyme and Ehrlich ascites tumor cell inhibitions

Studies on dehydrogenase enzyme inhibition have been extended with the design, synthesis, and correlation analysis of 7-[(substituted-benzyl)oxy]-, 7-[(substituted-phenethyl)oxy]-, and 7([substituted-phenoxy)ethoxy]-4-hydroxyquinoline-3-carboxylic acids. Sixteen new congeners and the fifteen molecules previously synthesized have been tested against cytoplasmic malate dehydrogenase and lactate dehydrogenase, as well as against mitochondrial malate dehydrogenase. The lipophilic congeners show a clear specificity for inhibition of the mitochondrial enzyme. Correlation analysis of the data on the three enzymes allows a comparison of the binding sites in quantitative terms, while examination of the data on inhibition of ascites tumor cell respiration affords an indication of membrane transport. A newly developed high-pressure liquid chromatography based retention index is compared to the octanol-water pi constant as a model for hydrophobic interactions.

Busulphan lung in childhood

A child receiving busulphan treatment for adult-type chronic myeloid leukaemia responded well for four years before the onset of complications leading to "busulphan lung'. Pulmonary function tests (PFT) were useful in monitoring the development of this condition and we recommended regular PFT for patient receiving busulphan treatment.

Renal lesion in Jeune's syndrome

In three children, presenting in chronic renal failure at the ages of six, four and three years radiology suggsested the diagnosis of Jeune's syndrome (asphyxiating thoracic dysplasia). In each case the skeletal survey showed widespread diagnostic features of this condition. The syndrome is characterized by varying degrees of repiratory distress in infancy and early childhood, with osseous dl three children in this study died from juvenile nephronopthisis. The correct diagnosis is essential for patient management and prognosis and also for genetic counselling. This report emphasizes the importance of the renal lesions in older children with Jeune's syndrome.

Allergic bronchopulmonary aspergillosis complicating cystic fibrosis in childhood

Allergic bronchopulmonary aspergillosis, known to be associated with cystic fibrosis in older patients, occurred in 7 young atopic children with cystic fibrosis. The diagnosis was suggested by the onset of, or the increase in, asthmatic symptoms accompanied by major chest x-ray changes ranging from total collapse of a lung or lobe to extensive but changing areas of consolidation. Each of the children had a blood eosinophilia, positive type I skin tests to Aspergillus fumigatus, and reversible airways obstruction. Most had a positive type III skin test and circulating precipitins to A. fumigatus, with raised IgE levels which contained specific antibodies to the fungus on radioallergosorbent (RAST) test. None had advanced suppurative chest disease of cystic fibrosis. None was given specific antifungal agents; two received systemic treatment with corticosteroids, the other received additional drugs for their asthma. Two developed total collapse of one lung, one child being only 2 years old. Five have had recurrences of pulmonary shadowing typical of allergic aspergillosis but are not showing significant progression of their cystic fibrosis lung disease. Our experience suggests that there should be an increased awareness of this condition, particularly its association with extensive pulmonary collapse or consolidation in children with cystic fibrosis who are atopic.

Clinical, haematological, and radiological features of children presenting with lymphoblastic mediastinal masses

During 1968-1978, 68 children presented in six centres in the United Kingdom with lymphoblastic mediastinal masses. The disease was classified as acute lymphoblastic leukaemia (ALL) in 49 children whose bone marrow aspirates contained > 20% lymphoblasts, and as lymphoma (Sternberg lymphosarcoma - LS) in 19 with < 20% marrow infiltration. Male predominated in both groups, and children with ALL had more visceromegaly and lymphadenopathy, lower haemoglobin levels and platelet counts, and higher white cell counts. The most common chest x-ray finding in both groups was a nonspecific anterior mediastinal mass, but the appearances varied considerably and could be classified into three categories, which are illustrated. Pleural effusions were present in 44%. Cell surface-marker studies showed T cell characteristics in 14 of the 17 patients tested. Response to treatment and complications, such as central nervous system (CNS) and testicular relapse, were similar in ALL and LS, and were related to the size of the initial tumour load. Median remission lengths were 37 weeks for ALL and 89 weeks for LS patients. Leukaemic transformation occurred in 47% of LS children. Compared with the outcome in ALL children without mediastinal mass, the results of treatment were poor, regardless of the protocol used, and prophylactic therapy to the CNS reduced the frequency of, but did not eliminate, CNS disease.

Necrotising entero-colitis following umbilical vein catheterisation

Fifteen cases of neonatal necrotising entero-colitis (NEC) following umbilical vein catheterisation are reported. Their clinical and radiological features are briefly described and the proper course of a catheter through the umbilical vein--ductus venosus--inferior vena cava segment is demonstrated. The significance of mal-position of the catheter and its association with NEC is discussed. It is suggested that the abdominal radiographs be taken in the antero-posterior and lateral projections with a portable X-ray machine to check the position of the radio-opaque catheter prior to the commencement of transfusion of infusion.

Clinical applications of serum carcinoembryonic antigen and alpha-fetoprotein levels in children with solid tumours

A study was carried out on serum carcinoembryonic antigen (CEA) and alpha-feto-protein (AFP) levels, both measured by radioimmunoassay, in 88 children with malignant solid tumours and in 26 children with nonmalignant disorders, who presented during the years 1973-77. Slightly or moderately raised CEA levels were found at presentation in 11 of 66 children with malignant tumours, in 2 others with recurrent tumours, and in 4 children with nonmalignant disorders. Raised CEA levels generally indicated advanced malignant disease, often affecting the liver, or other hepatic disorders, but were not associated with a specific tumour type. Except in the first months of life, significantly raised AFP levels were detected only in 11 patients with yolk sac-derived tumours, or hepatomas, and in one child with tyrosinosis who later developed a malignant hepatoma. Serial measurements of AFP accurately reflected the clinical response to treatment and in 2 patients indicated recurrence before this could be detected clinically.

Renal scarring and vesicoureteric reflux

A review of 105 children with urinary tract infection showed an increasing prevalence of grades II-III vesicoureteric reflux with diminishing age. During infancy reflux was almost always severe, and affected boys as often as girls. Radiologically scarred kidneys were drained by refluxing ureters in 98% of cases. The prevalence of scars also rose significantly with increasinglyly severe reflux. Deterioration of existing scars or new scar formation was seen in 15 children; 18 out of 20 affected kidneys (90%) were associated with grade III vesicoureteric reflux. 2 out of 5 children who developed new scars did so after 5 years of age. Because severe reflux may occasionally be seen in the presence of a normal intravenous urogram, and since the finding of grades II-III vesicoureteric reflux is an indication for chemoprophylaxis, we consider cystourethrography essential in children of all ages with recurrent urinary tract infection. In children under 5 years the increased prevalence of both severe reflux and renal scarring are arguments for regarding cystourethrography as a necessary initial investigation.

Giant-cell pneumonia caused by measles and methotrexate in childhood leukaemia in remission

Four children who had acurate lymphoblastic leukaemia in remission and developed pneumonia were studied. Investigations including electron microscopy and immunofluorescence of lung biopsy material disclosed measles, although there was no clinical evidence of the disease. Despite an identical presentation, two types of illness developed: two children died of giant-cell pneumonia, while the other two developed pneumonia indistinguishable from that associated with methotrexate treatment, recovering when treated with steroids and gammaglobulin. Measles infection is easily overlooked in the absence of rash. The diagnosis may be suggested by clinical and radiological features and confirmed by specific immunofluorescence staining of lung biopsy tissue.

Ascending uretero-pyelography in renal failure

Ascending uretero-pyelography has been carried out over a period of 13 years in 97 consecutive patients with undiagnosed renal failure. Sixty-nine were in a non-obstructive uropathy group while 26 had ureteric obstructions. There were two failures. Over 60% of examinations were performed under local anaesthesia, each examination taking an average of 20 min. There has been no mortality and two anaesthetic complications have been the only significant morbidity. Ureteric injury, urinary infection and renal function have all been investigated and recorded. Five per cent of patients developed urinary infection following AUP but without any major consequences. No significant ureteric injury occurred and no late sequelae were noted. Neither any reaction to contrast medium nor any further deterioration in renal function was observed; AUP was diagnostic in 46% of patients. In the remainder it ruled out obstructive uropathy and gave useful information about the kidneys, ureters and bladder. In experienced hands and with proper facilities AUP is safe and can be helpful in the diagnosis and management of patients in renal failure.

Design, synthesis, and correlation analysis of 7-substituted 4-hydroxyquinoline-3-carboxylic acids as inhibitors of cellular respiration

Fifteen 7-substituted 4-hydroxyquinoline-3-carboxylic acids have been designed to minimize covariance between the physicochemical substituent parameters: pi, MR, and sigmap. The molecules have been synthesized and evaluated for their ability to inhibit the respiration of Ehrlich ascites cells as a whole cell model and for their ability to inhibit malate dehydrogenase as an intracellular target enzyme model. Correlation analysis indicates that ascites cell inhibition is linearly related to pi and that malate dehydrogenase inhibition is linearly related to MR.