Patient-reported outcomes in major depressive disorder with suicidal ideation: a real-world data analysis using PatientsLikeMe platform

BACKGROUND

The current analysis utilized data collected via an online patient community platform, PatientsLikeMe (PLM) to compare patient-reported experiences in patients with major depressive disorder (MDD) with suicidal ideation (MDSI) to those with MDD but without suicidal ideation.

METHODS

PLM members who joined PLM between May-2007 and February-2018 and reported a diagnosis of MDD were included. The MDSI cohort included patients with MDD who reported at least one suicide-related symptom at a severity greater than "none". Demographics, comorbidities, symptoms, and side-effects were compared between MDSI and MDD cohorts. Factors correlated with suicidal ideation (SI) were determined by a random forest procedure.

RESULTS

Patients in the MDSI cohort (n = 266) were younger (median age, 36 vs 44 years) with an earlier disease onset (before 30 years, 83% vs 71%), and a longer diagnosis latency (median, 4 vs 2 years) vs patients in the MDD cohort (n = 11,963). Majority of patients were women in both cohorts (73% vs 83%). Median number of psychiatric comorbidities was higher in the MDSI cohort (4 vs 3). Unprompted symptoms (e.g., loneliness, feeling of hopelessness, social anxiety, impulsivity, and self-hating thoughts) were more frequent in the MDSI cohort. Hopelessness, loneliness, anhedonia, social anxiety, and younger age were highly correlated with suicidal ideation.

CONCLUSIONS

This analysis utilized patient-reported data to better understand symptoms, experiences, and characteristics of patients with MDSI compared to patients with MDD. The results identified various risk factors correlated with suicidal ideation that may help guide clinical judgement for patients with MDD who may not voluntarily report suicidal ideation.

Modeling of the hemodynamics in the feet of patients with peripheral artery disease

To simulate the hemodynamic effects in the feet in response to a thigh cuff occlusion, we have developed a multi-compartmental model in which the circulatory system for the leg is represented by its electrical equivalents. Dynamic vascular optical tomographic imaging data previously obtained from 20 patients with peripheral artery disease (PAD) and 20 healthy subjects is used to test the model. Analyzing the clinical data with the support of the model yields diagnostic specificity and sensitivity in the 90-95% range, significantly higher than previously reported.

Endovascular Treatment of False Aneurysm of the Thyrocervical Trunk

The thyrocervical trunk is the second superior branch off the subclavian artery. Pseudoaneurysm of the thyrocervical trunk has been reported after attempted internal jugular vein cannulation for central venous or hemodialysis access. The treatment of pseudoaneurysms of the thyrocervical trunk depends on the findings from color flow Doppler ultrasonography and angiography. Although pseudoaneurysms of the thyrocervical trunk are rare, the treatment options should be clear. Surgical ligation is an effective technique that is safe and well-defined, but control through a cervical incision may be difficult. Endovascular treatment of the pseudoaneurysm may be accomplished with coil embolization of the artery, which is described.

Detection of Peripheral Arterial Disease Within the Foot Using Vascular Optical Tomographic Imaging: A Clinical Pilot Study

OBJECTIVE

Vascular optical tomographic imaging (VOTI) is a novel imaging modality that is capable of detecting hemoglobin concentrations in tissue. VOTI is non-invasive, non-ionizing and does not require contrast injection. This technology was applied to the diagnosis of peripheral arterial disease (PAD) within lower extremities of diabetic patients with calcified arteries. This could be of substantial benefit as these patients suffer from comorbidities such as arterial incompressibility, which complicates diagnosis and monitoring.

METHODS

Forty individuals (10 non-diabetic patients with PAD, 10 diabetic patients with PAD, and 20 healthy volunteers) were enrolled in a diagnostic pilot study using the VOTI system. The patients were imaged during at high pressure cuff occlusion.

RESULTS

The VOTI system was capable of quantifying the blood volume changes within the foot during the thigh cuff occlusion and outputting diagnostic parameters, such as change in hemoglobin concentration, enabling the assessment of foot perfusion. This study resulted in a statistically significant difference between the healthy cohort and both the non-diabetic and the diabetic PAD cohorts (p = .006, p = .006). Receiver operating characteristic (ROC) curve analysis showed that PAD diagnosis could be made with over 80% sensitivity or specificity depending on the characteristic cutoff point. In addition, VOTI was capable of providing the locations of under-perfused regions within the foot and evaluating the severity of arterial disease, even within diabetic patients with calcified arteries, who are traditionally difficult to diagnose.

CONCLUSION

VOTI can effectively diagnose PAD independently of arterial compressibility, making it very useful for assessing vascular disease in diabetic patients.

Evaluation of the diagnostic value of immunocytochemistry and in situ hybridization in the pediatric leprosy

Leprosy is characterized by a long and variable incubation period and a chronic clinical course. Diagnosis of leprosy is essentially based on clinical features. Although the majority of cases can be diagnosed clinically yet alternative methods for diagnosis are required especially for early cases. Immunocytochemistry and in situ hybridization can be a valuable tool for diagnosis for early cases. The present study is aimed to assess the diagnostic value of immunocytochemistry and in situ hybridization in cytological specimens and to compare these techniques with Z.N. staining. This prospective study was carried out in 26 patients below 18 years of age of leprosy. Clinical examination of each patient was done and categorized according to IAL. After taking consent, three skin smears was taken, one for Z.N. staining and remaining two for immunocytochemistry and in situ hybridization respectively. Routine skin smear examination by Z.N. staining method confirmed the diagnosis in 4/26 (15.83%) and these belonged to BB, BL category. Immunocytochemistry showed positivity in 10/15 (66.6%) in BT and 72.7% in BB/BL leprosy. Immunocytochemistry improved the diagnosis by 53.85%, and the results were statistically significant (p < 0.01). In situ hybridization showed the positive results in 80% cases of BT leprosy and 90.9% cases of BB/BL leprosy. In situ hybridization improved the diagnosis by 70% in comparison to ZN staining and the results were statistically significant (p < 0.01). This study supports that immunocytochemistry and in situ hybridization enhance the diagnosis of leprosy when compared to routine skin smears stained by Z.N staining. They are important diagnostictoolsfor definitive diagnosis in early as well as established cases of leprosy.

Serological diagnosis of tuberculosis

OBJECTIVE

To evaluate the efficacy of ELISA for the detection of IgG antibodies against antigen 85 complex (Ag 85 complex) of Mycobacterium tuberculosis.

METHODS

Children of either sex, 0-18 years of age, attending the outpatient department and admitted in the casualty and wards of the Department of Pediatrics, S.N. Medical College, Agra, were included in present study. The study was carried out on children with pulmonary and CNS tuberculosis along with matching controls (83 cases and 32 controls). Informed consents of their parents or guardians were taken. They were subjected to clinical examination, relevant laboratory investigations, tuberculin test and chest radiograph. Relevant body fluids were subjected to bacteriological tests; ELISA was applied to serum samples for detection of IgG antibodies against antigen 85 complex (Ag85). The result of ELISA was compared with bacteriological tests [Ziehl Neelson (ZN) staining for acid-fast bacilli, culture on Lowenstein Jensen (LJ) medium and culture on BacT/Alert 3D system].

RESULTS

ELISA tests showed a significantly higher sensitivity (59.1%) as compared with LJ medium culture method (19.3%), BacT/Alert 3D system (24.1%) and ZN staining (16.9%) in all patients (p<0.001). Specificity of ELISA test was 71.9%.

CONCLUSION

In view of the convenience, low cost and good sensitivity, ELISA tests have a promising future in the diagnosis of childhood tuberculosis.

High Bifurcation of Brachial Artery With Acute Arterial Insufficiency: A Case Report

The upper extremity arterial system shows a large number of variations in the adult human body. Most of these variations occur in either the radial or ulnar artery; brachial artery variations are less common. Because the upper extremity is a frequent site of injury and various surgical and invasive procedures are performed in this region, it is of utmost importance to be aware of arterial variations. We report a case of a high bifurcation of the brachial artery presenting with acute ischemia secondary to an embolic event. The anomaly was identified, and the ischemia was successfully resolved with embolectomy.

Effect of therapy on serum zinc and copper in primary complex of children

Tuberculosis is a global problem especially in children, more so because of the difficulty in the diagnosis of the disease. There are about 0.5 million deaths every year by this disease, worldwide. There are some reports that, during the disease, there are changes in serum concentrations of zinc and copper, which reach towards normal levels during treatment. Such data for children are scarce, especially in reference to India. Our study indicates that there is an insignificant to significant rise in serum zinc levels in various age groups of children after antitubercular therapy (mean 61.89 +/- 3.21 to 65.24 +/- 3.60 microg/dl) and significant fall in serum copper levels in different age groups of children (mean 129.96 +/- 3.18 to 124.91 +/- 3.48 microg/dl). The Cu/Zn ratio also changed significantly from 2.11 +/- 0.12 to 1.92 +/- 0.12. Because evaluation of available diagnostic criteria for primary complex in children has been found to have high sensitivity, and although this criterion is presently not recommended for diagnosis of primary complex of children, further research can prove its utility in diagnosis and treatment of this disease.

PCR and in-situ hybridization for diagnosis of leprosy

OBJECTIVE

To assess the diagnostic value of Polymerase Chain Reaction (PCR) and in situ hybridization.

METHODS

This prospective study was carried out in 22 patients

RESULTS

The histopathological examination confirmed the clinical diagnosis in 27.2% cases only. In situ hybridization showed a positivity of 42.8% in early (I/BT) and 46.7% in BB/BL group. In situ hybridization thus enhanced the diagnosis by 18.1%. PCR targeting 36 kDa gene of M. leprae was performed on 15 cases. In these 15 cases, histopathology confirmed the diagnosis in 4 cases (26.6%) and PCR confirmed the diagnosis in 10 cases (66.6%), thus enhancing the diagnosis by 40%.

CONCLUSION

36 kDa PCR and in situ hybridization enhance the diagnosis of leprosy when compared to routine histopathology. They are important diagnostic tools for definitive diagnosis in early and doubtful cases of leprosy.

Diagnostic value of Elisa serological tests in childhood tuberculosis

Two separate studies (study I and study II) were conducted to evaluate the efficacy of ELISA serological test for the detection of IgG antibodies against specific glycolipid antigen (PGLTb1) and ESAT 6 antigen of Mycobacterium tuberculosis, respectively. These results were compared with bacteriological tests [Ziehl Neelson (ZN) staining for acid-fast bacilli and culture on Lowenstein Jensen (LJ) medium] and polymerase chain reaction (PCR) targeting IS6110 sequence. Both studies were carried out on children with pulmonary, central nervous system, lymph node, and gastrointestinal tuberculosis along with matching controls (65 cases and 27 controls for study I and 83 cases and 22 controls for study II). Informed consents of their parents or guardians were taken. They were subjected to clinical examination, relevant laboratory investigations, tuberculin test and chest radiograph. Relevant body fluids were subjected to bacteriological tests and PCR. Sera samples were analyzed for antibodies against PGLTbl and ESAT 6 antigen in study I and study II, respectively. ELISA tests showed a significantly higher sensitivity (49% study I; 53%, study II) as compared with LJ medium culture method (15.4%, study I; 28.9% study II) and ZN staining (27.7%, study I; 20.5%, study II) in all patients (p < 0.05). The results were comparable with PCR (40%, study I; 42.2% study II). Specificity of ELISA test was 100% in all the patients except in those with pulmonary disease (92.8%, study I; 84.8%, study II). In view of the convenience, low cost and comparable sensitivity with PCR, these ELISA tests have a promising future in the diagnosis of childhood tuberculosis.

Analysis of gene probes and gene amplification techniques for diagnosis and monitoring of treatment in childhood leprosy

Nucleic acid sequences of Mycobacterium leprae were detected using gene probes hybridizing with targeting ribosomal RNA (16S rRNA), ribosomal DNA (16S rDNA) and gene amplification techniques (PCR) in skin lesion of paediatric leprosy patients and the effect of treatment on the by these methods. Eighty paediatric leprosy patients were included in the study. Most cases (79%) were between 9 and 16 years of age. Cases were divided into three groups according to treatment status, viz. untreated (30), undergoing treatment (30), and at the end of treatment (20). Clinical and slit smear examination for acid fast bacilli (AFB) was performed and nucleic acids were extracted and fractionated from skin biopsies. M. leprae specific 16S rRNA and 16S rDNA was detected by hybridization with gene probes whereas the 36 kDa gene sequence was detected by a gene amplification assay (PCR). The cases were classified as paucibacillary (PB) and multibacillary (MB) by the standard criteria of WHO (1988). Positivity of 16S rRNA in PB cases decreased from 60% in untreated to 10.5% after 4-8 months of treatment whereas for 16S r DNA, it decreased from 50% to 21%, for PCR from 70% to 36.8% for the same specimen, and all became negative at 1 year. Similar trends were seen in MB cases where positivity in smear positive untreated cases decreased from 100% to 56.2% with 16S rRNA and 42.8% with 16S rDNA and PCR, respectively, after 9-12 months of treatment and all became negative at 2 years, except one case which remained positive with PCR. Similar results were observed in smear negative MB cases, 100% positivity detected by 16S r RNA and PCR, 75% detected by 16S rDNA decreased to zero after 9-12 months of therapy. This study suggests the potential usefulness of gene probes targeting 16S rRNA and 16S rDNA and PCR as supportive molecular tools for diagnosis of smear negative evolving MB disease and also monitoring the response to treatment, these observations however, needs to be validated in prospective follow up studies.

Diagnostic value of in situ Polymerase Chain Reaction in leprosy

OBJECTIVE

This prospective study was carried out to assess the diagnostic value of in situ Polymerase Chain Reaction in leprosy, particularly in enhancing the histopathological diagnosis.

METHOD

Clinical examination of 20 patients (< 16 yr) was done and skin smear for AFB was prepared. Biopsy of lesion site was taken for histopathological examination and in situ PCR testing.

RESULTS

The histopathological examination confirmed the clinical diagnosis in 45% cases only; non-specific histopathology was reported in the remaining 55% cases. In situ PCR showed a positivity of 57.1% in early/localized form of leprosy (IIBT) and 61.5% in (BB/BL) group. When compared to histopathology examination, a significant enhancement of 15% in diagnosis was seen. With in situ PCR, the diagnosis could be confirmed in 4/11 (36.3%) cases with non-specific histopathological features, (which is common in early disease) in addition to confirmation of 8/9 (88.8%) histopathologically-confirmed tissue sections. Histopathology and in situ PCR, combined together, confirmed the diagnosis in 13/20 cases (65% of total cases).

CONCLUSION

Thus, in situ PCR is an important diagnostic tool especially in early and doubtful cases of leprosy.

Endovascular stent graft selection for the treatment of abdominal aortic aneurysms

Minimally invasive endovascular techniques for the treatment of abdominal aortic aneurysms (AAA) have significantly reduced the morbidity of these procedures as compared with standard surgical repair. In addition, patients with extensive comorbid medical illnesses in whom standard operative repair is contra-indicated, may be successfully treated using endovascular means. A variety of endovascular stent grafts are currently being used clinically for endovascular AAA repair. The characteristics of these stent grafts vary significantly. In selecting the specific stent graft to be used for endovascular AAA repair, these specific characteristics must be considered particularly with regard to the individual patient's anatomic and physiologic characteristics. The United States Food and Drug Administration (FDA) has approved 4 endovascular stent grafts for the treatment of AAA: the Medtronic AneuRx, the W. L. Gore Excluder, the Cook Zenith and the Guidant Ancure. The Zenith graft received approval for marketing in 2003 and has gained relatively wide usage, in part due to its ability to treat aneurysms with relatively large diameter implantations zones. Also in 2003 the Guidant Corporation withdrew the Ancure graft from marketing and distribution. Enrollment has also been recently completed for the phase II FDA trials of the Medtronic Talent graft and the Cordis Fortron graft. These devices have been approved for use in the European Union and are awaiting FDA panel meeting in the United States. Comparative analysis of several of the available stent grafts has been performed. Results have varied with regard to the need for secondary interventions, aneurysm sac size reduction and the occurrence of continued perfusion of the aneurysm sac. Several significant advances have also occurred recently in stent graft research and development. Of particular significance has been the initiation of the phase I trial of the Trivascular Enovus graft. Deployment of the Trivascular graft may be accomplished through a delivery system that is considerably reduced in profile. The potential for percutaneous application of the graft may be available in the future. The indications for use of endovascular grafts as compared to standard open surgery have not yet been fully defined. Endovascular stent grafts in current use have limitations and their use must be tempered accordingly, until their long-term effectiveness is more completely evaluated. This article describes the general principles of use for endovascular devices for the repair of AAAs. It details the features and results for the devices in current use and highlights the factors that influence the selection of specific stent graft types.

GC-MS analysis of essential oils of heartwood and resin of Shorea robusta

The essential oils of Shorea robusta heartwood and resin were isolated by hydrodistillation of their respective petroleum ether extracts. Nine and seventeen compounds representing 80.35 % and 78.43 % of the oil, respectively were identified by GC-MS. Germacrene-D was found to be the chief constituent of both the oils. This is the first report on heartwood and resin oils of Shorea robusta.

Complement degradation product C3d in urine: marker of lupus nephritis

OBJECTIVE

To examine whether serum and urine C3d, a degradation product of C3, correlate with renal and extrarenal lupus activity.

METHODS

Serum and urinary C3d levels were measured by ELISA in 15 healthy individuals and 24 patients with systemic lupus erythematosus (SLE) (8 with inactive disease, 7 with active but nonrenal disease, 9 with active lupus nephritis). Disease activity variables like serum C3, C4, and anti-dsDNA antibodies were also measured.

RESULTS

The median serum C3d levels were significantly higher (p < 0.01) in patients with active (26 arbitrary units/ml; AU/ml) and inactive SLE (27 AU/ml) compared to healthy controls (11.25 AU/ml); levels were comparable in patients with active renal and extrarenal SLE. On the other hand, urine C3d was elevated only in patients with active SLE; its level was highest in patients with active lupus nephritis (0.87 AU/ml) compared to patients with active extrarenal diseases (0.31 AU/ml; p < 0.05), to patients with inactive lupus nephritis (0.06 AU/ml; p < 0.001), or to levels in healthy individuals (0.06; p < 0.001). Urine C3d showed stronger correlation with disease activity score (SLE Disease Activity Index) than serum C3, C4, anti-dsDNA antibodies, and serum C3d.

CONCLUSION

Urine C3d is a good index of active lupus, particularly lupus nephritis.

Isolation and identification of 4,25-dihydroxyvitamin D2: a novel A-ring hydroxylated metabolite of vitamin D2

Vitamin D2 is less toxic in rats when compared to vitamin D3. Our laboratory has been involved in research projects which were directed towards identifying the possible mechanisms responsible for the toxicity differences between vitamins D2 and D3 in rats. The present research project was designed to isolate and identify new metabolites of vitamin D2 from serum of rats which were fed toxic doses of vitamin D2. Hypervitaminosis D2 was induced in 30 rats by feeding each rat with 1000 nmol of vitamin D2/day x 14 days. The rats were sacrificed on the 15th day and obtained 180 ml of serum. The lipid extract of the serum was directly analyzed by a straight phase HPLC system. The various vitamin D2 metabolites were monitored by their ultraviolet (UV) absorbance at 254 nm. One of the UV absorbing peaks did not comigrate with any of the known vitamin D2 metabolites. This unknown metabolite peak was further purified by HPLC and was then subjected to UV absorption spectrophotometry and mass spectrometry. The structure assignment of the new metabolite was established to be 4,25-dihydroxyvitamin D2 [4,25(OH)2D2] by the techniques of UV absorption spectrophotometry and mass spectrometry and by the new metabolite's susceptibility to sodium metaperiodate oxidation. At present the biological activity of this unique 'A-ring' hydroxylated vitamin D2 metabolite is not known. As this new metabolite is isolated from the serum of rats intoxicated with vitamin D2, we speculate that 4,25(OH)2D2 may be playing an important role in the deactivation of vitamin D2.

Volatile constituents of Vitex negundo leaves

Volatile constituents of Vitex negundo leaves growing in Dehra Dun (India) were analysed by gas chromatography-mass spectrometry (GC-MS) and showed the presence of sixty-six compounds. Such a study has not been done earlier on the Indian oil. Thirty-five compounds, constituting 74.96% of the oil, were identified. The main compounds are viridiflorol (19.55%), beta-caryophyllene (16.59%), sabinene (12.07%), 4-terpineol (9.65%), gamma-terpinene (2.21%), caryophyllene oxide (1.75%), 1-oceten-3-ol (1.59%), and globulol (1.05%). Viridiflorol is being reported for the first time in the oil of Vitex species.

NPY upregulates genes containing cyclic AMP response element in human neuroblastoma cell lines bearing Y1 and Y2 receptors: involvement of CREB

Four NPY receptor subtypes have been cloned, and shown to be coupled to both Ca2+ and cAMP. However, very little is known about the downstream elements mediating NPY actions. It has recently been demonstrated in our laboratory that intrahypothalamic (i.h.t.) administration of NPY induces hypothalamic CaM kinase activity, cyclic AMP response element binding protein (CREB) phosphorylation and cyclic AMP response element (CRE) binding activity in rat hypothalamic nuclear proteins. In the present study, we have investigated whether these changes in CRE binding transcriptional factors activated by NPY results in gene regulation using a human neuroblastoma cell line (SK-N-BE2). This cell line which expresses the Y2 subtype of NPY receptors was transfected with a fusion gene containing 1.305 kb of human CRF 5' flanking region with a perfect palindromic CRE site linked to firefly luciferase gene. NPY treatment increased CaM kinase II activity, CREB phosphorylation and CRE binding in these cells. In transfected cells, luciferase activity was also increased by NPY (1.8-4-fold) within 4 h of treatment. Moreover, forskolin (7-30-fold), which stimulates cAMP production, and thapsigargin (6-8-fold), which mobilizes intracellular calcium, also increased luciferase activity within 4 h of treatment. PMA (phorbol-12-myristate-13-acetate), an activator of protein kinase-C, induced luciferase activity by 1.8-fold. NPY augmented forskolin-stimulated luciferase activity from 11- to 15-fold, but had no significant effect on thapsigargin-induced luciferase activity. These findings suggest that activation of protein kinase A (PKA) or CaM kinase leads to the induction of fusion gene. NPY treatment upregulated fusion gene expression through Ca2+ pathway in SK-N-BE2 cell line. Pretreatment with CREB antisense, but not the sense oligodeoxynucleotides, inhibited forskolin-, thapsigargin- and NPY-stimulated luciferase activity. However, CREB sense or antisense oligodeoxynucleotide treatment had no effect on PMA-stimulated luciferase activity. Furthermore, NPY induced CRE binding activity and the expression of CRE containing Y1 receptor gene in SK-N-MC cell line. These findings suggest that NPY can upregulate CRE containing reporter gene including Y1 receptor gene and NPY-induced reporter gene regulation in SK-N-BE2 cells is mediated by intracellular Ca2+ and CREB protein.

Study of gene probes in childhood leprosy

The objective was to detect nucleic acids of M. leprae in skin lesions of leprosy patients and study the effect of treatment on these nucleic acids, using r-RNA gene probes, using a cross sectional study. The study was carried out at Department of Paediatrics, S.N. Medical College, Agra and Department of Microbiology, Central JALMA Institute for leprosy, Agra. The study included 32 cases of leprosy less than 16 years of age, divided into 3 groups viz. without treatment (12 cases), in middle of treatment (11 cases) and at the end of treatment (9 cases). All cases were subjected to a detailed history and thorough clinical examination. All of them had smear examination and lepromin test done and their skin biopsies were subjected to gene detection. Nucleic acids were isolated from skin biopsies of all cases by standard procedure. After dot blotting of these nucleic acids, they were hybridised with radioactive (p32) r-RNA probes. The results were interpreted after getting the X-ray films processed with background signals from controls. Majority of cases were between 13-16 years of age. As age advanced, the disease moved from tuberculoid end of spectrum towards lepromatous end (p < 0.05). Majority of paucibacillary (PB) cases were lepromin positive while majority of multibacillary (MB) cases were lepromin negative (p < 0.05). In specimens of untreated cases, 50% of PB specimens and 87.5% of MB specimens were positive for r-RNA probes. In multibacillary type 100% smear positive specimens and 67% smear negative specimens were positive for r-RNA probes. In patients during the middle of treatment positivity for r-RNA decreased and 20% of PB specimens and 16.6% MB specimens were positive. At the end of treatment (1 year for PB cases and 2 years for MB cases), the results of r-RNA were negative, which indicated that the treatment regimens used in the study were effective. This study supports the usefulness of r-RNA probes as a diagnostic and therapeutic tool in childhood leprosy.

Is undifferentiated seronegative spondyloarthropathy a forme fruste of reactive arthritis?

Undifferentiated spondyloarthropathy (USpa) may either represent a forme fruste of other spondyloarthropathies like reactive arthritis or be a different disease entity. To study the link between USpa and reactive arthritis, we studied the presence of IgA antibodies to Yersinia enterocolitica, Salmonella typhimurium, Shigella flexneri, Campylobacter jejuni and Chlamydia trachomatis in sera from 14 patients with USpa (European Spondyloarthropathy Study Group criteria) using ELISA. Escherichia coli was used as a control antigen. An OD value of more than the mean +/- 2 S.D. of 51 blood donors was considered positive. Five patients had elevated IgA antibodies to S. flexneri, while two patients each had elevated antibody levels to S. typhimurium and Chlamydia. No patient had elevated antibodies to Y. enterocolitica, C. jejuni and E. coli. Among 51 normals, 1, 4, 3, 2 and 3 had elevated antibodies to S. flexneri, S. typhimurium, Y. enterocolitica, C. jejuni and E. coli, respectively. Nine of 14 patients with USpa had antibodies to one of the bacteria implicated in reactive arthritis: of these, antibodies to Shigella were the most frequent. Thus, a proportion of patients with USpa may in fact have reactive arthritis.

Prevention and early detection of leprosy in children

India with its 4 million cases of leprosy, accounts for one-third of the world's population of leprosy patients. One-fourth of them are below 15 years of age. We report a 5-year follow-up study of healthy children who were close contacts of leprosy patients, in order to: 1. detect subclinical infection and observe the development of overt disease by using the Fluorescent Leprosy Antibody Absorption Technique (FLA-ABS) and the lepromin test which assess the humoral and cell-mediated immunity (CMI), respectively; 2. evaluate the efficacy of dapsone as a chemoprophylactic agent in the 'at risk' contacts. Four-hundred-and-fifty-five healthy contacts were studied. Majority of the contacts of multibacillary patients (303) were FLA-ABS positive (75 percent) and lepromin negative (55 percent) showing that although most of them had been infected, the lepromin status was negative (P < 0.01). On the other hand, the majority of the contacts of paucibacillary patients (152) were lepromin positive (57 percent) (P < 0.05). Furthermore, only 61 percent of contacts of paucibacillary patients were FLA-ABS positive as compared to 75 percent of contacts of multibacillary patients demonstrating that the former had been exposed to a lesser quantum of infection (P < 0.05). On the basis of results of FLA-ABS and lepromin tests, these 455 contacts were classified into four groups, viz. Group I comprising children who were FLA-ABS positive and lepromin positive; Group II, who were FLA-ABS positive and lepromin negative; Group III, who were FLA-ABS negative and lepromin positive; and Group IV who were FLA-ABS negative and lepromin negative.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnostic value of gene probes and its correlation with clinical profile of leprosy in children

Clinico-bacteriological profile of 73 leprosy patients below 16 years of age was studied. Majority of the patients were males and fell in 11-16 years age group (p < 0.05). Skin lesions were present in all cases on both exposed as well as unexposed areas and their number increased with advancing age. Cutaneous sensations were affected in most of the patients while nerve thickening was observed in 41. As age increased, the disease moved from the tuberculoid end of spectrum towards the lepromatous end (p < 0.05) and the positivity of the skin smears increased (p < 0.05). Majority of the paucibacillary cases were lepromin positive while most multibacillary cases were lepromin negative (p < 0.01). Two M. leprae specific gene probes were applied in 42 cases to assess their diagnostic value. Eighty one per cent cases were picked up by the probes indicating presence of active bacilli. These included all lepromin positive cases, all smear positive cases, and most of smear negative cases (p < 0.05). Seven children with inconclusive histology were also positive. Drug treatment and inadequate size of biopsy sample could explain the negative probe results in 19% cases. This study highlights the immense potential of gene probes in diagnosing leprosy in children.

Hypothalamic concentration and release of neuropeptide Y into microdialysates is reduced in anorectic tumor-bearing rats

Hypothalamic concentration of neuropeptide Y was decreased significantly in anorectic tumor-bearing rats, while NPY level was increased significantly in matched carcass weight control rats as compared with freely-feeding controls. In vivo microdialysis of the perifornical hypothalamic area of tumor-bearing rats prior to the development of anorexia revealed no alteration in NPY in dialysates. Following the development of anorexia, however, tumor-bearing rats exhibited significant reduction in NPY concentration in dialysates as compared with either matched carcass weight or freely-feeding control group. These results suggest that hypothalamic NPY concentration and release are decreased selectively in anorectic tumor-bearing rats. Since NPY also elicits less feeding in tumor-bearing rats, dysfunction of hypothalamic NPY feeding mechanisms may be of primary importance in cancer anorexia.

Airway secretion clearance by mechanical exsufflation for post-poliomyelitis ventilator-assisted individuals

Pulmonary complications from impaired airway secretion clearance mechanisms are major causes of morbidity and mortality for post-poliomyelitis individuals. The purpose of this study was to review the long-term use of manually assisted coughing and mechanical insufflation-exsufflation (MI-E) by post-poliomyelitis ventilator-assisted individuals (PVAIs) and to compare the peak cough expiratory flows (PCEF) created during unassisted and assisted coughing. Twenty-four PVAIs who have used noninvasive methods of ventilatory support for an average of 27 years, relied on methods of manually assisted coughing and/or MI-E without complications during intercurrent respiratory tract infections (RTIs). Nine of the 24 individuals were studied for PCEF. They had a mean forced vital capacity (FVC) of 0.54 +/- 0.47L and a mean maximum insufflation capacity achieved by air stacking of ventilator insufflations and glossopharyngeal breathing of 1.7L. The PCEF were as follows: unassisted, 1.78 +/- 1.16L/sec; following a maximum assisted insufflation, 3.75 +/- 0.73L/sec; with manual assistance by abdominal compression following a maximum assisted insufflation, 4.64 +/- 1.42L/sec; and with MI-E, 6.97 +/- 0.89L/sec. We conclude that manually assisted coughing and MI-E are effective and safe methods of airway secretion clearance for PVAIs with impaired expiratory muscle function who would otherwise be managed by endotracheal suctioning. Severely decreased maximum insufflation capacity but not vital capacity indicate need for a tracheostomy.

Addition of lipid to total parenteral nutrition prevents hepatic steatosis in rats by lowering the portal venous insulin/glucagon ratio

Hepatic steatosis in rats is associated with an infusion of excessive carbohydrate calories. Previous work from this laboratory suggested that this is associated with an elevated portal insulin/glucagon molar ratio (I/G) and is reversed by parenteral glucagon administration. Although hepatic steatosis is not related to essential fatty acid deficiency, addition of lipid to total parenteral nutrition (TPN) has been reported as being protective against the development of hepatic steatosis. Therefore, we propose that lipid may exert its salutary effect via an alteration of the I/G ratio. To test this hypothesis, adult rats (seven per group) received internal jugular catheters: group 1, saline (3 mL/h) plus chow ad libitum; group 2, 25% dextrose base TPN; group 3, 17% dextrose base TPN + 2.5% lipid; group 4, 25% dextrose base TPN + 2.5% lipid. At 7 days, portal and peripheral venous blood was drawn for insulin and glucagon radioimmunoassay and liver function tests; livers were removed for histology and lipid content determination. Panlobular vacuolization, on histology, and lipid content were excessive in group 2, and the portal I/G was increased because of elevated portal insulin. In contrast, portal venous insulin and I/G did not increase, and hepatic steatosis was absent in groups 3 and 4. The results suggest that the addition of lipid to TPN in rats decreases the portal insulin level and lowers the portal I/G, and thereby prevents hepatic steatosis.

Early detection of leprosy in children

Healthy children contacts of leprosy patients had their humoral and cell-mediated immunological status assessed using the Fluorescent Leprosy Antibody Absorption Technique (FLA-ABS) and the Lepromin test, respectively. Subsequently, they were followed up for 2 1/2 years to study the development of overt disease. Two-hundred children were studied and classified into four groups, viz. Group I comprised of children who were FLA-ABS positive and Lepromin positive; Group II = FLA-ABS positive and Lepromin negative; Group III = FLA-ABS negative and Lepromin positive; Group IV = FLA-ABS negative and Lepromin negative. The good cell-mediated immune (CMI) response in the 107 children in Group I prevented them from developing the disease though they had been infected. Out of the 37 children in Group II, 15 developed the disease. There were no children in Group III. None of the 56 children in Group IV developed the disease, possibly because they had not been significantly infected. All these findings were statistically significant (P less than 0.01). This study highlights the protective role of cell-mediated immunity in leprosy. It also suggests the need to carry out surveillance surveys in the endemic population to identify and follow up those at risk.

Effects of glucose on circulating and ileal intraluminal peptide YY and pancreatic polypeptide release

Peptide YY (PYY) and pancreatic polypeptide (PP) are related hormones released systemically after a meal. The effects of glucose stimulation and vagal involvement on circulating and ileal luminal PYY and PP concentrations were evaluated in awake dogs. An oral glucose tolerance test (OGTT), intravenous glucose tolerance test (IVGT), 2-deoxyglucose bolus (2-DG), or atropine pretreatment prior to OGTT were administered to awake dogs with 25-cm ileal Thiry-Vella fistulas. Circulating and ileal intraluminal PYY and PP levels were measured by radioimmunoassay. No changes were noted in circulating PYY, and circulating PP increased (p less than 0.05) only after administration of 2-DG. Ileal luminal PP recovery was minimal (less than 60 pg/mL) and was unchanged after all tests. Ileal luminal PYY recovery increased significantly after both OGTT and IVGT. Pretreatment with atropine abolished the luminal PYY response to OGTT, and 2-DG did not affect luminal PYY recovery. Blood glucose and insulin levels were similar in all groups. Peripheral cholinergic control of luminal PYY release is suggested by our findings, whereas a central mediation of circulatory PP release is supported by 2-DG stimulation.

Oxidative denitrification of 2-nitropropane and propane-2-nitronate by mouse liver microsomes: lack of correlation with hepatocytotoxic potential

2-Nitropropane (2-NP) is an industrial chemical with hepatotoxic and genotoxic properties. It exists in chemical equilibrium with propane-2-nitronate, which is much more genotoxic than 2-NP. In this work the link between toxicity and metabolism of 2-NP and its nitronate was investigated. To that end 2-NP or propane-2-nitronate were incubated with murine hepatic microsomes at concentrations of up to 10 mM, and generation of nitrite was measured as product of metabolic oxidation of the two species. Under the acidic reaction conditions of the colorimetric nitrite assay propane-2-nitronate decomposed chemically to nitrite. Therefore an ion-pair HPLC assay at neutral pH was developed which enabled determination of nitrite formed from the nitronate. The rate of metabolic nitrite generation from propane-2-nitronate was 5-10-fold that obtained with 2-NP. Metabolism of either species to nitrite was dependent on the presence in the incubate of viable microsomes and of NADPH, and it was inhibited in the presence of carbon monoxide or the cytochrome P-450 inhibitor SKF525A. Acetone could also be measured as a metabolite of 2-NP. Optical difference spectra were recorded in mixtures of propane-2-nitronate with liver microsomes from phenobarbital-pretreated rats. The spectral dissociation constant was found to be 30 mM, which compares with 10 mM reported for 2-NP. 2-NP and propane 2-nitronate were incubated with mouse hepatocytes in suspension and cytotoxicity was determined by measurement of leakage of cellular lactate dehydrogenase into the medium. Both species were hardly toxic, as concentrations of 20 mM were required to elicit significant damage to the cells. The results demonstrate that propane-2-nitronate, like 2-NP, undergoes microsomal oxidative denitrification, probably catalysed by cytochrome P-450. Metabolism of both species occurs at markedly different rates, but the difference in metabolism is not reflected by a difference in hepatocytotoxic potential.

N-alkylformamides are metabolized to N-alkylcarbamoylating species by hepatic microsomes from rodents and humans

Hepatotoxic formamides such as N-methylformamide (NMF) and N,N-dimethylformamide (DMF) are metabolized in vivo to N-acetyl-S-(N-methylcarbamoyl)cysteine via oxidation at the formyl carbon, which yields a reactive intermediate. The hypothesis was tested that this biotransformation route can be studied in vitro with hepatic fractions. NMF was incubated with microsomes or cytosol obtained from BALB/c mice, and metabolically generated N-methyl-carbamoylating species were analyzed after derivatization with ethanol in base to furnish ethyl N-methylcarbamate. Generation of metabolite was catalyzed by microsomes, but not by cytosol. Detection of the N-methylcarbamoylating species was dependent on the presence in the incubation mixture of NMF, viable microsomes, NADPH, and a thiol-containing agent such as glutathione. Metabolite formation was inhibited by SKF 525-A (3 mM) and abolished when the incubation atmosphere consisted of an air/carbon monoxide mixture (1:1) instead of air. Metabolism was not induced by pretreatment of mice with phenobarbital or beta-naphthoflavone. N-Ethylformamide and the DMF metabolite N-(hydroxymethyl)-N-methylformamide, but not DMF, were metabolized by microsomes to the N-alkylcarbamoylating metabolite at a measurable rate. NMF metabolism was also observed with liver microsomes from Sprague-Dawley rats or from humans. In the case of rat microsomes the rate of metabolism was half of that measured with murine microsomes. The results suggest that (i) the metabolic toxification of NMF can be studied in hepatic microsomes and (ii) the oxidation of the formyl moiety in N-alkylformamides is catalyzed by cytochrome P-450.

Endogenous peptide YY is dependent on jejunal exposure to gastrointestinal contents

Peptide YY (PYY), a homolog of pancreatic polypeptide, has been shown to be released after stimulation of colonic mucosa with bile and fatty acids. In this study proximal jejunal and biliary involvement in the regulation of circulating PYY and the distribution of PYY-containing cells in rat intestine was evaluated. Six rats underwent proximal jejunal bypass, six rats had Roux-en-Y cholangiojejunostomies, and six sham-operated rats were used as controls. Three months after surgery feeding studies using either a mixed meal or a pure fat meal were performed in unanesthetized animals and venous blood was collected for plasma PYY radioimmunoassays. After the feeding studies, fresh specimens were taken from multiple areas of the intestine for immunohistochemical analysis. The surgical procedures did not significantly affect basal PYY plasma levels. Both mixed and fat meals significantly increased circulating PYY in control animals. Exclusion of the proximal jejunum resulted in inhibition of postprandial PYY release. The PYY response in rats with Roux-en-Y cholangiojejunostomies was blunted after a mixed meal and delayed after a fat meal. The incidence of PYY-containing cells increased along the functional gut in all rats. The bypassed jejunum in both experimental groups of animals contained fewer PYY-staining cells than sham-operated rats. Our results suggest that the exclusion of a segment of proximal jejunum from gastrointestinal continuity in rats leads to an inhibition of postprandial PYY release. PYY release may be controlled in part by stimulatory neural and/or endocrine signals originating from the proximal jejunum.

Addition of L-glutamine to total parenteral nutrition and its effects on portal insulin and glucagon and the development of hepatic steatosis in rats

Infusion of total parenteral nutrition (TPN) with excess carbohydrate calories leads to hepatic steatosis in rats and is associated with an elevated portal insulin/glucagon molar ratio. Previously we have shown that adding glucagon to TPN prevents and reverses hepatic steatosis in rats, possibly by increasing hepatic lipid export. It has been reported that steatosis is eliminated in rats by the addition of L-glutamine to TPN. In this study, we examined the effect of glutamine on portal insulin and glucagon levels and the development of hepatic steatosis. Adult rats (n = 19) received internal jugular catheters: Group 1 (n = 6), saline (3 cc/hr) and chow ad libitum; Group 2 (n = 7), 25% dextrose base TPN; Group 3 (n = 6), 25% dextrose base TPN with 2% glutamine. The infusion rate of TPN was 1.2 cc/100 g body wt/hr. Daily nitrogen balance was determined and at 7 days, portal venous blood was drawn for insulin and glucagon radioimmunoassay, livers were removed for histology and lipid content determination, and the small intestines were removed for mucosal protein and DNA content determination. Panlobular vacuolization of the hepatocytes was noted on histology in Group 2 (TPN) while Group 1 (chow) and Group 3 (TPN + glutamine) showed normal liver morphology. Hepatic lipid content was significantly elevated in Group 2 (P less than 0.05). The portal insulin/glucagon molar ratio was increased because of excessive portal venous insulin in Group 2 (TPN). In contrast, portal glucagon was significantly elevated while the insulin/glucagon ratio and hepatic lipid content did not increase above control levels in the glutamine-supplemented Group 3 rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Chemical synthesis and cytotoxic properties of N-alkylcarbamic acid thioesters, metabolites of hepatotoxic formamides

The S-linked cysteine and glutathione conjugates of N-methylformamide and N-ethylformamide, together with a series of methyl ester derivatives thereof, have been synthesized and characterized by 1H NMR, 13C NMR, FAB-MS, and FAB tandem mass spectrometry. In vitro cytotoxicity assays showed that all of the title conjugates were toxic to isolated mouse hepatocytes when incubated at concentrations in excess of 1 mM and that they served as potent growth inhibitors of murine TLX5 lymphoma cells when present at levels of 10-100 microM. Both of these effects were reversed by the addition to incubation media of glutathione (10 mM). The possibility is raised that N-alkylcarbamic acid thioester conjugates, which are formed during the metabolism of N-alkylformamides in mammalian systems, may act as important mediators of the antineoplastic and/or hepatotoxic activity of the parent formamides, possibly through their ability to liberate methyl isocyanate at cell membranes.

Radioimmunoassay to determine postprandial changes in plasma neuropeptide Y levels in awake dogs

A specific, precise and sensitive double-antibody radioimmunoassay for Neuropeptide Y (NPY) has been developed. There was no appreciable cross-reactivity with the structurally related peptides, peptide YY (PYY) and pancreatic polypeptide (PP). The minimum detectable plasma NPY level was 3 nM. Application of radioimmunoassay to canine models revealed that portal and systemic NPY levels increased significantly following a standard meal.

Comparison of the hepatotoxicity in mice and the mutagenicity of three nitroalkanes

The hepatotoxic and mutagenic potentials of 2-nitropropane, nitromethane, and nitroethane were compared. Hepatotoxicity was assessed biochemically and histopathologically in BALB/c mice. In male mice, plasma activities of the hepatic enzymes sorbitol dehydrogenase, alanine aminotransferase, and aspartate aminotransferase were significantly elevated 48, 72, and 96 hr after ip administration of 9 mmol/kg 2-nitropropane, but not at 24 hr and not after administration of smaller doses of 2-nitropropane nor after nitromethane or nitroethane (9 mmol/kg). In female mice a dose of 6.7 mmol/kg of 2-nitropropane was sufficient to cause hepatotoxicity. The histopathological evaluation supported the biochemical results, and livers of mice that had received 2-nitropropane (9 mmol/kg) showed damage, particularly in the periportal region. Mutagenicity was tested in Salmonella typhimurium tester strains TA98, TA100, and TA102. Both 2-nitropropane and its anionic form, propane-2-nitronate, were mutagenic but the nitronate was the more powerful mutagen. Nitromethane, nitroethane, nor their nitronates caused an increase in the number of revertant colonies over those seen in control plates. The results suggest that the primary nitroalkanes are much less hepatotoxic and mutagenic than 2-nitropropane.

Reversal of hepatic steatosis in rats by addition of glucagon to total parenteral nutrition (TPN)

Infusion of total parenteral nutrition (TPN) with excess carbohydrate calories leads to hepatic steatosis in rats that is associated with an elevated portal insulin/glucagon molar ratio. Previously we have shown that adding glucagon to TPN prevents hepatic steatosis in rats. In this study we attempted to reverse the steatosis by adding glucagon to TPN after 1 week of TPN alone. Adult rats (n = 28) received internal jugular catheters: Group 1 (n = 7), saline (3 cc/h) and chow ad libitum; Group 2 (n = 7), 25% dextrose base TPN solution for 1 week; Group 3 (n = 7), 25% dextrose base TPN for 2 weeks; Group 4 (n = 7), 25% dextrose base TPN for 1 week and then glucagon (15 micrograms/100 g/day) added to TPN for the second week. The infusion rate of TPN was 1.2 ml/100 g/hr (40% kcal greater than control). At 7 days (Group 2) and 14 days (Groups 1, 3, and 4) portal and peripheral venous blood levels were drawn for insulin and glucagon radioimmunoassay, blood glucose determination, and liver function tests; livers were removed for histology and lipid content determination. Blood glucose was equivalent among all groups. Liver function tests were within normal limits. Panlobular vacuolization of the hepatocytes was noted on histology in Groups 2 and 3. Hepatic lipid content was significantly elevated in Group 3. The portal insulin/glucagon molar ratio was increased because of excessive portal venous insulin in Groups 2 and 3 (P less than 0.05 by ANOVA). In contrast, portal venous insulin and the insulin/glucagon molar ratio did not increase in Group 4 and hepatic lipid infiltration was absent when glucagon was added to the TPN solution after 1 week of TPN solution alone. The results suggest that the addition of glucagon to hypertonic dextrose TPN is not only protective in preventing hepatic steatosis, but may reverse steatosis, possibly by increasing hepatic lipid export.

Hydatid disease: analysis of parasite antigens in circulating immune complexes and in preformed hydatid antigen-antibody complexes

Fifty-three sera from 29 patients with hydatid disease, all but one positive for specific anti-parasite antibodies and all negative for specific circulating antigens, were studied for the presence of circulating immune complexes (CIC) by conglutinin binding-assay (KgBA). Fourteen serum samples (26%) from eight patients (27%) were positive. These positive sera were pooled for each patient and the eight samples were PEG-precipitated and analysed for the presence of specific Echinococcus granulosus antigens in the CIC using a human anti-human-hydatid cyst fluid antiserum capable of recognizing the major antigenic systems of the parasite namely, antigens 4 and 5. The assays utilized for detecting antigen in CIC were: (a) blotting on nitrocellulose paper after sodium dodecil sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and specific immunological detection; (b) ultracentrifugation in acid buffer and subsequent detection of antigens by a sandwich-radioimmuno assay (RIA); (c) protein separation by isoelectric focusing (IEF) and specific immunological recognition. In addition, all positive sera were analysed for the presence of antigen in the CIC by a modified KgBA and by polyethylenglicol (PEG)-precipitation in acid buffer followed by immunological recognition of antigen. All tests gave negative results with the patients' samples, but were positive with preformed in vitro complexes between parasite antigens and corresponding antibodies. Failure to detect antigen in the CIC could be due to: 1) insufficient sensitivity of the assays used to detect hydatid antigens in CIC; 2) rapid clearance of antigen or CIC from the circulation; 3) presence of parasite antigen not recognized by the antiserum employed; 4) production of CIC as a result of polyclonal B-cell activation. This last hypothesis is supported by the demonstration of IgM-rheumatoid factor (RF) and anti-F(ab')2 antibodies respectively in 11 (44%) and 13 (52%) out of 25 patients.

A clinico-bacteriological profile of leprosy in children

Clinico-bacteriological profile of 106 leprosy patients below 15 years of age was studied. Majority of the patients were males and fell in the 10-15 years age group (p less than 0.01). Nearly 89% had not received any prior treatment because of financial constraints. Seventy per cent gave a positive history of contact with adult patients who were mainly of the lepromatous variety (p less than 0.01). Skin lesions were present in 103 cases, mainly on the exposed areas and their number was found to increase significantly with advancing age (p less than 0.01). These lesions were hypopigmented patches in 71% of the children and erythematous in the rest. Cutaneous sensations were affected in most of the patients while nerve thickening was observed in 45. Positivity of the skin smears increased significantly as the number of skin lesions per patient increased (p less than 0.05). With advancing age, the disease moved from the tuberculoid end of the spectrum towards the lepromatous end (p less than 0.01).

Addition of glucagon to total parenteral nutrition (TPN) prevents hepatic steatosis in rats

Hepatic steatosis is one of the two principal hepatic complications of total parenteral nutrition (TPN), the other being cholestasis. While the cause is uncertain, an excess of carbohydrate calories in rats leads to an elevated portal insulin/glucagon (I/G) molar ratio, periportal fatty infiltration, and increased total hepatic lipid content. Insulin causes fatty acid biosynthesis, whereas glucagon causes hepatic release and inhibition of fatty acid synthesis. Thus we attempted to add glucagon to lower the I/G to see if this would affect the degree of hepatic fatty infiltration by encouraging hepatic fat mobilization. Adult rats (n = 21) received internal jugular catheters; Group 1 (n = 7) was given saline solution (3 ml/h) and chow ad libitum; Group 2 (n = 7), 25% dextrose-base (D25W) TPN solution; Group 3 (n = 7), D25W TPN + 33 micrograms/100 gm/day glucagon. At 7 days portal and peripheral venous blood samples were drawn for insulin and glucagon radioimmunoassay and blood glucose determination; livers were removed for histologic study and lipid determination. Blood glucose did not differ in any group. Hepatic lipid and peripheral and portal venous I/G were increased and periportal fatty infiltration was extensive in Group 2, whereas hepatic lipid and I/G were decreased and periportal fatty infiltration was absent in glucagon-infused rats (Group 3). An abnormally high I/G ratio in portal blood elicited by high-glucose TPN may be responsible, at least in part, for hepatic steatosis. By increasing hepatic lipid export, addition of glucagon to TPN may play a major role in decreasing hepatic steatosis.

Increasing dextrose concentrations in total parenteral nutrition (TPN) causes alterations in hepatic morphology and plasma levels of insulin and glucagon in rats

Hepatic steatosis is an ongoing problem in total parenteral nutrition (TPN). The etiology of this deranged hepatic morphology is unclear, but lack of enteral stimulation and excess carbohydrate calories have been suggested as altering the intestinal hormone profile. In this study, adult male Sprague-Dawley rats (n = 28) received internal jugular catheters: group 1 (n = 7) received saline (3 cc/hr) and chow ad libitum; groups 2, 3, and 4 (n = 7) received 15, 20, and 25% dextrose-base TPN solutions, respectively, in quantities matching the caloric intake of paired ad libitum animals. At 7 days portal and peripheral venous blood samples were drawn for insulin and glucagon radioimmunoassay, and livers were removed for histologic examination and determination of total hepatic lipid content. Portal and peripheral insulin levels rose in a linear fashion with increasing dextrose concentration. Lipid content increased with elevated portal venous insulin/glucagon ratio in groups 3 and 4. Periportal fatty infiltration increased with increasing dextrose concentrations. The results suggest that the liver's response to altered portal insulin/glucagon ratio may play an important role in changes of hepatic morphology associated with TPN.

Isolation and identification of 1,23-dihydroxy-24,25,26,27-tetranorvitamin D3, a new metabolite of 1,25-dihydroxyvitamin D3 produced in rat kidney

A new metabolite of vitamin D3 was produced in vitro by perfusing rat kidneys with 1,25-dihydroxyvitamin D3 (4 X 10(-6) M). It was isolated and purified from the lipid extract of the kidney perfusate by high-performance liquid chromatography. By means of ultraviolet absorption spectrophotometry, mass spectrometry, chemical derivatization, and chemical synthesis, the new metabolite was identified as 1,23-dihydroxy-24,25,26,27-tetranorvitamin D3. Along with the new metabolite, three other previously identified metabolites, namely, 1,24,25-trihydroxyvitamin D3, 1,25-dihydroxy-24-oxovitamin D3, and 1,23,25-trihydroxy-24-oxovitamin D3, were also isolated. The new metabolite was also formed when 1,23,25-trihydroxy-24-oxovitamin D3 was used as the substrate. Thus, the new metabolite fits into the following metabolic pathway: 1,25-dihydroxyvitamin D3----1,24(R),25-trihydroxyvitamin D3----1,25-dihydroxy-24-oxovitamin D3----1,23,25-trihydroxy-24-oxovitamin D3----1,23-dihydroxy-24,25,26,27-tetranorvitamin D3. Further, we used 1 alpha,25-dihydroxy[1 beta-3H]vitamin D3 in the kidney perfusion system and demonstrated 1,23-dihydroxy-24,25,26,27-tetranorvitamin D3 as the major further metabolite of 1,25-dihydroxyvitamin D3, circulating in the final perfusate when kidneys were perfused with 1,25-dihydroxyvitamin D3 (6 X 10(-10) M) for 4 h. The biological activity of 1,23-dihydroxy-24,25,26,27-tetranorvitamin D3 (C-3 alcohol) and its metabolic relationship to 1-hydroxy-23-carboxy-24,25,26,27-tetranorvitamin D3 (calcitroic acid or C-23 acid), the other previously identified side-chain cleavage metabolite of 1,25-dihydroxyvitamin D3, are unknown and are presently undergoing investigation.