Estradiol alleviates depressive-like symptoms in a novel animal model of post-partum depression

The effect of hormone withdrawal following hormone-simulated "pregnancy" on "depressive-like behavior" in the Forced Swim Test (FST) was investigated in female Long-Evans rats. Females were randomly assigned to "pregnant", "pregnant"+estradiol benzoate (EB), and control groups. Both the "pregnant" and "pregnant"+EB groups received daily injections of the hormones estradiol and progesterone to simulate the 23-day gestational period in the rat. However, the "pregnant"+EB group continued to receive daily estradiol injections after "pregnancy". All groups were tested 48 h after the last injection of the pregnancy period in the FST and subsequently in the Open Field Test (OFT). Results revealed that the "pregnant" rats exhibited significantly increased immobility and decreased struggling and swimming behaviors as compared to the "pregnant"+EB and control groups. These findings could not be explained by an overall depression in general locomotor activity among "pregnant" rats, as the "pregnant" rats made more area crossings in the OFT. Thus "pregnant" rats exhibited behaviors consistent with "depressive-like" symptoms "post-partum" (after their hormone regime was discontinued). Continual treatment with high levels of estradiol in the "pregnant"+EB group, however, reversed the exhibition of these behaviors. These results imply that withdrawal from chronic high levels of pregnancy-associated hormones (estradiol and progesterone) can produce depressed symptomology in rodents, which can be prevented by prolonging exposure to high levels of estradiol through the post-partum period. These findings are the first demonstration of "depressive-like" symptoms in a rodent model of post-partum pregnancy and the ability of high levels of estradiol to attenuate these "depressive-like" symptoms.

Antidepressant-like actions of pregnancy, and progesterone in Wistar rats forced to swim

In rats, some behavioral changes occurring during pregnancy related to the presence of progesterone may be analyzed in the forced swimming task (FST), which is designed to test the antidepressant profile of drugs. The present study was aimed to analyze in pregnant rats, in rats after delivery, or in rats after receiving progesterone those behavioral changes displayed in the FST. We hypothesize that pregnancy and progesterone will produce antidepressant-like effects in rats forced to swim. Therefore, pregnant rats (14th, 17th, and 20th days), or rats after delivery (3rd, and 7th days) were tested in the FST. Ovariectomized rats receiving saline (0.9%; i.p.), clomipramine (1.25 mg/kg; i.p.), or desipramine (2.14 mg/kg; i.p.) for 28 days were also tested in the FST. In a second series of experiments, ovariectomized rats receiving vehicle or progesterone (0.5 mg/kg; or 2.0 mg/kg; sc.) were tested in the FST. Locomotion was evaluated in the open field test. Results showed that in the FST: 1) pregnancy (P < 0.05), or progesterone (P < 0.05), or desipramine (P < 0.05), reduced immobility by increasing climbing; 2) clomipramine (P < 0.05) reduced immobility by increasing swimming; 3) rats tested after delivery displayed similar behavior than control rats. A lower locomotion was observed only at the end of pregnancy. In conclusion, results suggest that during pregnancy, a reproductive process characterized by its high levels of progesterone, antidepressant-like effects can be found.

Bioavailability and pharmacokinetic features of etoposide in childhood acute lymphoblastic leukemia patients

The bioavailability and pharmacokinetic characteristics of etoposide were studied in 12 relapsed B-lineage acute lymphoblastic leukemia (ALL) patients after both intravenous (i.v.) infusion and oral administration. Following a 1 hour i.v. infusion of 50 mg/m2 etoposide, the elimination half-life ranged from 49.8 min to 509.4 min (mean +/- SD = 218.6 +/- 134.7 min), the MRT ranged from 71.8 to 734.9 min (mean +/- SD = 315.4 +/- 194.3 min) and the systemic clearance of etoposide ranged from 15.7 to 38.0 ml/min/m2 (mean +/- SD = 24.1 +/- 7.0 ml/min/m2). The AUC ranged from 2234.9 to 5427.0 microM.min) (mean +/- SD = 3827.8 +/- 1069.5 microM.min) and Vc ranged from 2026.9 to 13,505.2 ml/m2 (mean +/- SD = 6825.4 +/- 3278.5 ml/m2). The maximum plasma etoposide levels ranged from 6.0 to 28.4 microM (mean +/- SD = 13.6 +/- 6.3 microM). The bioavailability of oral etoposide was determined by comparing the AUC following i.v. infusion to the AUC following oral administration in the same patient. The overall bioavailability (mean +/- SD) was 60.6 +/- 22.4% (ranged from 17.6% to 91.2%). The elimination half-life following oral administration (mean +/- SD) was 209.8 +/- 196.3 min (ranged from 51.0 to 794.2 min). The time required to reach the maximum plasma etoposide concentration was 145.4 +/- 118.7 min (ranged from 23.7 to 396.9 min). To our knowledge, this is the first report concerning the bioavailability of etoposide in pediatric leukemia patients. All of the other pharmacokinetic properties of etoposide in pediatric B-lineage ALL leukemia patients reported here were similar to those described previously.

Genetic variations and polymorphisms of G protein-coupled receptors: functional and therapeutic implications

G protein-coupled receptors (GPCRs) represent a major class of proteins in the genome of many species, including humans. In addition to the mapping of a number of human disorders to regions of the genome containing GPCRs, a growing body of literature has documented frequently occurring variations (i.e. polymorphisms) in GPCR loci. In this article, we use a domain-based approach to systematically examine examples of genetic variation in the coding and noncoding regions of GPCR loci. Data to date indicate that residues in GPCRs are involved in ligand binding and coupling to G proteins and that regulation can be altered by polymorphisms. Studies of GPCR polymorphisms have also uncovered the functional importance of residues not previously implicated from other approaches that are involved in the function of GPCRs. We predict that studies of GPCR polymorphisms will have a significant impact on medicine and pharmacology, in particular, by providing new means to subclassify patients in terms of both diagnosis and treatment.

Antibody, cytokine and cytotoxic T lymphocyte responses in chimpanzees immunized with human papillomavirus virus-like particles

We evaluated antibody, cytokine (IFN-gamma, IL-5, TNF-alpha), and cytotoxic T lymphocyte (CTL) responses in chimpanzees immunized with monovalent or quadrivalent (HPV-6, -11, -16, -18) L1 virus-like particle (VLP) vaccines administered i.m. on aluminum hydroxyphosphate (alum) at weeks 0, 8 and 24. Maximum serum antibody titers to type-specific, neutralizing, conformational epitopes on HPV-11 or -16 L1 VLPs were detected by radioimmunoassay (RIA) four weeks after the second and third immunizations. HPV-11 and -16 neutralizing antibodies were also detected at similar time points with an Human papillomaviruses (HPV) neutralization assay using pseudovirions. Depending on the VLP type used for immunization, HPV type-specific cytokine responses were most frequently seen four weeks after the second or third immunizations and between weeks 44-52. Transient HPV-16 L1-specific CTL activity was observed only between weeks 16-24 in 3 of 22 (13.6%) chimpanzees immunized with HPV-16 L1 VLPs. These findings provide evidence that immunization with multivalent L1 VLPs on alum can evoke both neutralizing antibodies and Th1 and Th2 cytokine responses to several HPV types; however, induction of CTLs is infrequent.

PNA oligomers as tools for specific modulation of gene expression

Small synthetic molecules that can specifically inhibit translation and/or transcription have shown great promise as potential antisense/antigene drugs. Peptide nucleic acid (PNA), an oligonucleotide mimic, has a non-charged achiral polyamide backbone to which the nucleobases are attached. PNA oligomers are extremely stable in biological fluids and they specifically hybridise to DNA or RNA in a complementary manner, forming very strong heteroduplexes. Some of the mRNAs have yet undetermined and possibly long half-lives, successful down regulation of gene expression by antisense oligonucleotides (ON) requires that the antisense agent is long lived. PNA fulfils this requirement better than phosphodiester or phosphorothioate ONs. PNA can inhibit transcription and translation of respective genes by tight binding to DNA or mRNA. First in vitro experiments to specifically down regulate protein expression by PNA have been followed by successful antisense and antigene application of PNA oligomers in vivo. This review discusses the principles of the in vitro and in vivo use of PNA oligonucleotides.

Hydrosalpinx and assisted reproduction: options and rationale for treatment

Salpingoscopy during laparoscopy yields the best prognosis in patients with hydrosalpinx. It has been demonstrated that in-vitro fertilization (IVF) patients with hydrosalpinx have decreased pregnancy rates as compared with control individuals. If a patient with hydrosalpinx is to be treated with IVF, then the communication between the uterine tube and the uterine cavity should be blocked via salpingectomy or proximal tubal ligation, with or without distal tubal fenestration. This is because there is evidence that hydrosalpinx, especially when it is bilateral and visible by ultrasonography, impacts negatively on pregnancy and implantation rates after IVF cycles.

A review of the new minimally invasive brain stimulation techniques in psychiatry

New knowledge about the specific brain regions involved in neuropsychiatric disorders is rapidly evolving due to recent advances in functional neuroimaging techniques. The ability to stimulate the brain in awake alert adults without neurosurgery is a real advance that neuroscientists have long dreamed for. Several novel and minimally invasive techniques to stimulate the brain have recently developed. Among these newer somatic interventions, transcranial magnetic stimulation (TMS), vagus nerve stimulation (VNS) and deep brain stimulation (DBS) show promise as therapeutic tools in the treatment of neuropsychiatric disorders. This article reviews the history, methodology, and the future of these minimally invasive brain stimulation (MIBS) techniques and their emerging research and therapeutic applications in psychiatry

Treatment of hydrocephalus in adults by placement of an open ventricular shunt

OBJECT

Ventricular shunt placement is the neurosurgical procedure most frequently associated with complications. Over the years, it has been a growing concern that the performance of most shunting devices does not conform to physiological parameters. An open ventriculoperitoneal (VP) bypass with a peritoneal catheter for which the cross-sectional internal diameter was 0.51 mm as a distinctive element for flow resistance was evaluated for use in the treatment of adult patients with hydrocephalus.

METHODS

During a 2-year period, open shunts were surgically implanted in 54 adults with hydrocephalus; conventional shunts were implanted in 80 matched controls. Periodic evaluations were performed using neuroimaging studies and measures of clinical status. All patients were followed from 12 to 36 months. 18.5 +/- 4 months for patients with the open shunt and 19.1 +/- 8.1 months for controls (mean +/- standard deviation). The device continued to function in 50 patients with the open shunt (93%) and in 49 controls (61%: p < 0.001). The Evans index in patients with the open shunt was 0.33 +/- 0.09 throughout the follow up. No cases of infection, overdrainage, or slit ventricles were observed: the index in controls was 0.28 +/- 0.08; 60% of them developed slit ventricles. During the follow-up period occlusion occurred in four patients with the open shunt (7%) and in 31 controls (39%: p < 0.001).

CONCLUSIONS

The daily cerebrospinal fluid (CSF) drainage through the open VP shunt is close to 500 ml of uninterrupted flow propelled by the hydrokinetic force generated by the combination of ventricular pressure and siphoning effect. It complies with hydrokinetic parameters imposed by a bypass connection between the ventricular and peritoneal cavities as well as with the physiological archetype of continuous flow and drainage according to CSF production. The open shunt is simple, inexpensive, and an effective treatment for hydrocephalus in adults.

Receptores acoplados à proteína G: implicações para a fisiologia e doenças endócrinas

A maioria dos hormônios polipeptídicos e mesmo o cálcio extracelular atuam em suas células-alvo através de receptores acoplados à proteína G (GPCRs). Nos últimos anos, tem sido freqüente a identificação e associação causal de mutações em proteínas G e em GPCRs com diversas endocrinopatias, como diabetes insipidus nefrogênico, hipotiroidismo familiar, puberdade precoce familiar no sexo masculino e nódulos tiroidianos hiperfuncionantes. Nesta revisão, abordamos aspectos referentes ao mecanismo de transdução do sinal acoplado à proteína G, e descrevemos como mutações em GPCRs podem levar a algumas doenças endócrinas. Finalmente, comentamos a respeito das implicações diagnósticas e terapêuticas associadas com o maior conhecimento dos GPCRs.

Effects of nicotine on ethanol dependence and brain damage

Almost all alcoholics (80%-95%) smoke tobacco. When alcoholics binge, they achieve high, sustained blood alcohol levels, become physically dependent, and often suffer loss of cognition and other higher cortical functions. Nicotine could have a modulatory effect on ethanol drinking behavior and ethanol-induced brain damage through its cholinergic actions. To determine whether nicotine altered alcohol dependence, alcohol-induced brain damage, or both, a rat model of binge drinking was used to study the effects of nicotine on the alcohol withdrawal syndrome and its associated brain damage. After administration of the last dose of ethanol in a 4-day binge model, rats remained intoxicated for approximately 5 h, slowly returned to a neutral state, and entered a hyperexcited period, which peaked around 24 h and lasted a total of 60 h. Behavioral signs of withdrawal included splayed limbs, tremors, and seizures. Continuous transdermal nicotine did not alter the duration or severity of ethanol withdrawal. The 4-day binge ethanol treatment caused considerable brain damage in the perirhinal cortex, entorhinal cortex, ventral dentate gyrus, and olfactory bulb as visualized with amino cupric silver stain. Nicotine alone caused little or no brain damage and did not markedly alter binge ethanol-induced damage in cortical or hippocampal regions. In the olfactory bulb, nicotine reduced ethanol-induced brain damage. Although results of other studies seem to indicate that nicotine increases alcohol consumption, our findings indicate that nicotine does not markedly change the development of alcohol dependence or alcohol-induced cortical damage.

Microsurgical DREZotomy for pain due to spinal cord and/or cauda equina injuries: long-term results in a series of 44 patients

According to the literature estimations, 10-25% of patients with spinal cord and cauda equina injuries eventually develop refractory pain. Due to the fact that most classical neurosurgical methods are considered of little or no efficacy in controlling this type of pain, the authors had recourse to microsurgery in the dorsal root entry zone (DREZ). This article reports on the long-term results of the microsurgical approach to the dorsal root entry zone (DREZotomy) in a series of 44 patients suffering from unbearable neuropathic pain secondary to spine injury. The follow-up ranged from 1 to 20 years (6 years on average). The series includes 25 cases with conus medullaris, 12 with thoracic cord, four with cauda equina and three with cervical cord injuries. Surgery was performed in 37 cases at the pathological spinal cord levels that corresponded to the territory of the so-called 'segmental pain', and in seven cases, on the spinal cord levels below the lesion for 'infralesional pain' syndromes. The post-operative analgesic effect was considered to be 'good' when a patient's estimation of pain relief exceeded 75%, 'fair' if pain was reduced by 25-75%, and 'poor' when the residual pain was more than 75% of preoperative estimations. Immediate pain relief was obtained in 70% of patients and was long-lasting in 60% of the total series. The results varied essentially according to the distribution of pain. Good long-term results were obtained in 68% of the patients who had a segmental pain distribution, compared with 0% in patients with predominant infralesional pain. Regarding pain characteristics, a good result was obtained in 88% of the cases with predominantly paroxysmal pain, compared with 26% with continuous pain. There were no perioperative mortalities. Morbidity included cerebrospinal fluid leak (three patients), wound infection (two patients), subcutaneous hematoma (one patient) and bacteremia (in one patient). The above data justify the inclusion of DREZ-lesioning surgery in the neurosurgical armamentarium for treating 'segmental' pain due to spinal cord injuries.

Tuberculous peritonitis--reports of 26 cases, detailing diagnostic and therapeutic problems

OBJECTIVE

To evaluate the clinical presentation, biochemical (ascites and serum) and laparoscopic findings, and to assess the efficacy of triple antituberculous therapy without rifampicin for 6 months in patients with tuberculous peritonitis.

METHODS

Twenty-six tuberculous peritonitis patients (11 male, 15 female) with a mean age of 34.8 +/- 3.4 years (range 14-77) were assessed with regard to diagnostic and therapeutic features.

RESULTS

The most common symptoms and signs were abdominal pain (92.3%) and ascites (96.2%), respectively. Tuberculin skin test (TST) was positive in all patients. An abnormal chest radiography suggestive of previous tuberculosis was present in five patients (19.2%), and two patients (7.7%) had extra-peritoneal (cerebral, pericardial) active tuberculous involvement. In 24 of the 25 patients who underwent laparoscopy with directed biopsy, whitish nodules suggested tuberculous peritonitis; 76% of the biopsy specimens revealed caseating, 20% non-caseating granulomatous inflammation, and 4% non-specific findings. The ascitic fluid of one patient (3.8%) was positive for acid-resistant bacilli, and culture was positive in two patients (7.7%). Twenty-four of the patients were treated for 6 months with isoniazid, streptomycin (total dose 40 g) and pyrazinamide (for the first 2 months and then substituted with ethambutol). Eighteen patients also received methyl prednisolone, initially 20 mg/day, for 1 month. The follow-up period was 19 +/- 1.7 months after the end of therapy (range 6-36). Ascites and abdominal pain abated earlier in patients on steroid therapy. All but two of the 24 patients responded to treatment.

CONCLUSION

Non-invasive tests such as acid-fast stain and culture of the ascitic fluid are usually insufficient, hence invasive laparoscopy and peritoneal biopsy are necessary for the diagnosis of tuberculous peritonitis if non-invasive tests such as ascites adenosine deaminase activity measurement are not easily available. Triple therapy without rifampicin for 6 months is sufficient to treat tuberculous peritonitis.

Non-hyperfunctioning nodules from multinodular goiters: a minor role in pathogenesis for somatic activating mutations in the TSH-receptor and Gsalpha subunit genes

Constitutive activation of the cAMP pathway stimulates thyrocyte proliferation. Gain-of-function mutations in Gsalpha protein have already been identified in thyroid nodules which have lost the ability to trap iodine. In contrast, most of the studies failed to detect somatic activating mutations in the thyrotropin receptor (TSH-R) in non-hyperfunctioning thyroid tumors. The aim of this study was to screen for mutations TSH-R exon 10, encoding the whole intracytoplasmic area involved in signal transduction, and Gsalpha exons 8 and 9, containing the two hot-spot codons 201 and 227, in a subset of non-hyperfunctioning nodules from multinodular goiter. Identified by matching ultrasonography and scintiscan, 22 eufunctioning (normal 99Tc uptake) and 15 nonfunctioning (decreased 99Tc uptake) nodules from 27 non-toxic multinodular goiters were isolated. After DNA extraction, TSH-R exon 10 was analyzed by direct sequencing of the PCR products and Gsalpha exons 8 and 9 by Denaturing Gradient Gel Electrophoresis. No mutation of TSH-R or Gsalpha was detected in the 37 nodules analyzed. This absence of mutation, despite the use of two sensitive screening methods associated with the analysis of the TSH-R whole intracytoplasmic area and Gsalpha two hot-spot codons, suggests that TSH-R and Gsalpha play a minor role in the pathogenesis of non-toxic nodules from multinodular goiters.

Functional, molecular, and biochemical characterization of streptozotocin-induced diabetes

Altered divalent cation homeostasis with bone mineral loss, hypercalciuria, and hypomagnesemia have been associated consistently with human diabetes mellitus. This study investigated functional, molecular, and biochemical determinants that accompany this condition in chronically (2 wk) streptozotocin (STZ)-diabetic rats. Catheterized, conscious, diabetic rats on servo-controlled fluid replacement exhibited an increased GFR (+70%) and a substantially raised urinary calcium output (+568%) when compared with control rats. In addition, fractional calcium reabsorption was reduced, indicating that the hypercalciuria was not due solely to an osmotic effect but may involve an actual tubular defect. The expression of proteins involved in renal distal Ca2+ and water transport in STZ-diabetic rats were then studied by Western analysis and immunofluorescence microscopy to investigate the molecular basis of the hypercalciuria. Extracellular Ca2+-sensing receptor abundance was reduced to 52% of control in STZ-diabetes, whereas thiazide-sensitive NaCl cotransporter expression was increased by 192%. Subcutaneous insulin implant rectified both functional and molecular parameters. The levels of calbindin D(28k), plasma membrane Ca2+ ATPase, and aquaporin 1 in whole kidney and of aquaporin 2 in inner medulla were unchanged in diabetic and/or insulin replacement. Blood levels of 1,25(OH)(2)D(3) were reduced in diabetes as were levels of osteocalcin, a marker of bone formation. It is concluded that diabetic hypercalciuria in rats involves elevated GFR with raised urinary output, reduced Ca2+ reabsorption, and impaired bone deposition. Changes in Ca2+-sensing receptor and NaCl cotransporter protein expression could account for the altered divalent cation homeostasis seen during diabetes mellitus.

Results of an outpatient-based stem cell allotransplant program using nonmyeloablative conditioning regimens

Using nonmyeloablative, immunosuppressive, fludarabine (FLU)-based conditioning regimens, we have performed allogeneic peripheral blood stem cell transplants in 26 patients (8 with chronic myelogenous leukemia, 6 with acute myelogenous leukemia, 10 with acute lymphoblastic leukemia, 1 with myelodysplasia, and 1 with thalassemia major). Conditioning consisted of FLU/busulphan/cyclophosphamide/cyclosporin-A (CyA)/methotrexate, or FLU/melphalan/CyA/methotrexate. The median granulocyte recovery time to 0.5 x 10(9)/l was 11 days, whereas the median platelet recovery time to 20 x 10(9)/l was 12 days. Twelve patients did not need red blood cell transfusions, and 8 did not need platelet transfusions. In 21 individuals (81%), the procedure could be completed fully on an outpatient basis. Follow-up times range between 30 and 600 days: one patient failed to engraft and recovered endogenous hemopoiesis; six out of 26 patients developed acute graft-versus-host disease (GVHD) whereas 7/22 developed chronic GVHD. Twelve patients (46%) have died, nine of them with a relapsing disease and three with GVHD; median post-transplant survival (SV) was 300 days, whereas the 12-month SV was 42%. The 100-day mortality was 3.8% and the transplant-related mortality was 11.5%. This procedure is substantially less costly than its counterpart, using in-hospital myeloablative conditioning regimens, and it may represent another approach in the management of patients requiring an allogeneic stem cell transplant.

Genetic Variation among Human Isolates of Uninucleated Cyst-Producing Entamoeba Species

Twelve human infections with Entamoeba spp. producing uninucleated cysts were studied. DNA was extracted from infected feces and used to amplify part of the ameba small-subunit rRNA gene. Sequence analysis identified four distinct types of Entamoeba, all of which are related to Entamoeba polecki and E. chattoni and two of which have not been reported previously. Whether these genetic types represent different species is unclear. We propose that the agent of all human infections with uninucleated cyst-producing Entamoeba species be reported as "E. polecki-like."

Fractionated doses of oral etoposide in the treatment of patients with aids-related kaposi sarcoma: a clinical and pharmacologic study to improve therapeutic index

The purpose of this study was to examine the antitumor activity, toxic effects, and plasma pharmacokinetics of fractionated doses of oral etoposide aiming at the achievement of prolonged safe and active plasma drug levels in patients with AIDS-related Kaposi sarcoma (KS). This was designed as a phase II trial in which consecutive patients with progressing AIDS-KS after at least 3 months of active antiretroviral therapy received oral etoposide at the dose of 20 mg/m2 every 8 hours daily for 7 days every 21 days, with the study of its plasma pharmacokinetics. Eligible patients were 18 to 60 years old, with a histopathologically confirmed diagnosis of AIDS-related KS, human immunodeficiency virus-positive test, progressing after at least 3 months of active antiretroviral therapy, World Health Organization (WHO) performance status 0 to 3, New York University staging IIA or greater, no active infection except oral candidiasis, normal bone marrow, liver, and renal function, and who signed an informed consent. Objective tumor responses were evaluated after at least one full treatment course according to a modified WHO criteria, and toxicity was evaluated weekly and graded using the National Cancer Institute-Common Toxicity Criteria (NCI-CTC) criteria. For the pharmacokinetic study, plasma was obtained from patients during the first drug administration immediately before and at various time points thereafter. Etoposide was measured after extraction from plasma by a standard high-performance liquid chromatography. Twenty-one patients were accrued for the study, and 18 of them met the eligibility criteria. They were all men, with median age of 36 years old (range: 25-50 years), median WHO performance status 0 (range: 0-3) median CD4+ count (cells/mm3) 67 (range: 8-443), prior AIDS diagnosis in 10 of 18 cases, NYU staging IIA (1 patient), IIB (1), IIIA (7), IIIB (1), IVA (4), and IVB (4) sites of disease: mucocutaneous only (5), mucocutaneous/lymph nodes (5), mucocutaneous/lung (5) and mucocutaneous/lymph nodes/lung (2); and prior cytotoxic treatment in two patients. Seventy-two percent of cases presented some form of toxic effect (NCI-CTC). Leukopenia was documented in 50% of cases, anemia occurred in 61%, whereas thrombocytopenia was documented in 17% of the patients. The main nonhematologic toxicities were nausea and vomiting in 17% of cases and alopecia in 44%. The overall objective response rate was 83%, with 2 complete remissions documented (11%). The median duration of responses was 12 weeks (range: 3-45 weeks). The median t1/2 of etoposide in plasma was 4.11 hours (range: 1.95-9.64), area under the curve was 13.51 microg/h/ml (range: 7.12-24.42), Cmax was 2.17 microg/ml (1.40-4.41), tmax (1.00-2.00), mean residence time 4.62 hours (range: 3.75-5.20 hours), CIt (total clearance) 3.13 l/m2/h (range: 1.49-5.20 l/m2/h), Vd 13.08 l/m2 (range: 6.23-19.65 l/m2), and the median etoposide plasma concentration time greater than 1 microg/ml was 3.69 hours (range: 1.00-6.80 hours). The use of fractionated oral daily doses of etoposide produced significant antitumor activity with manageable clinical toxicity in the individuals with AIDS-KS included in this trial. This more favorable therapeutic index of etoposide could be due to the achievement of more sustained plasma levels of the drug within safe but active concentrations.

Do helminths play a role in carcinogenesis?

Chronic helminthiasis is recognized as a significant factor in cancer development in humans. However, the mechanisms by which helminths initiate and promote malignant transformation of host cells are still not understood fully. Human helminthiasis can cause genetic instability and affect inter- and intracellular communication, ultimately leading to tumour development through inflammation, modulation of the host immune system, and secretion of soluble factors that interact with host cells.

Small Intestinal Infections

The differential diagnosis of small intestinal infections is broad, making the identification and management of these disorders challenging. The majority of cases of acute diarrhea are self-limited and do not require diagnostic evaluation or treatment. Most patients do not require specific therapy, and treatment should focus on fluid and electrolyte replacement. In patients with severe, persistent, or chronic diarrhea, a careful medical history and routine stool testing are helpful in determining the cause. Pathogen-specific therapy should be given in patients in whom a pathogen is identified. In those without an identifiable pathogen, antidiarrheal agents are helpful in reducing the number of bowel movements and preventing further dehydration. Endoscopy may be helpful in patients with severe diarrhea and a negative stool evaluation, particularly in HIV-infected patients with chronic diarrhea. Surgery has a limited role in the management of small intestinal infections, but may be lifesaving in patients with intestinal perforation or small bowel obstruction.

A review of hepatitis E virus

Hepatitis E virus (HEV) is a major cause of outbreaks and sporadic cases of viral hepatitis in tropical and subtropical countries but is infrequent in industrialized countries. The virus is transmitted by the fecal-oral route with fecally contaminated drinking water being the usual vehicle. Hepatitis resulting from HEV infection is a moderately severe jaundice that is self-limiting in most patients. Young adults, 15 to 30 years of age, are the main targets of infection, and the overall death rate is 0.5 to 3.0%. However, the death rate during pregnancy approaches 15 to 25%. Death of the mother and fetus, abortion, premature delivery, or death of a live-born baby soon after birth are common complications of hepatitis E infection during pregnancy. Hepatitis E virus is found in both wild and domestic animals; thus, HEV is a zoonotic virus. The viruses isolated from swine in the United States or Taiwan are closely related to human HEV found in those areas. The close genetic relationship of the swine and human virus suggests that swine may be a reservoir of HEV. In areas where swine are raised, swine manure could be a source of HEV contamination of irrigation water or coastal waters with concomitant contamination of produce or shellfish. Increasing globalization of food markets by industrialized countries has the potential of introducing HEV into new areas of the world. The purpose of this review is to cover certain aspects of hepatitis E including the causative agent, the disease, diagnosis, viral detection, viral transmission, epidemiology, populations targeted by HEV, and the role of animals as potential vectors of the virus.

Concepts and methods in chronic thalamic stimulation for treatment of tremor: technique and application

OBJECTIVE

To rationalize the technique and reduce the costs associated with chronic deep brain stimulation of the thalamus for treatment of refractory tremor.

METHODS

The efficacy and safety of a modification in surgical techniques was prospectively assessed in 94 patients with tremor. Bilateral electrodes were implanted in 29 patients, and 65 patients received unilateral implants. Forty-five patients had Parkinson's disease tremor, 42 patients had essential tremor, and 7 patients had kinetic tremors of different causes. In all instances, intraoperative stimulations to analyze the thresholds of intrinsic and extrinsic responses were performed directly with the implanted leads. The electrodes were repositioned until satisfactory results were achieved. The pulse generators were implanted directly after the first step in the same operative session. Patients were not subjected to interoperative test stimulation trials.

RESULTS

Postoperative improvement of tremor at a mean follow-up of 11.9 months was rated as excellent in 47 patients (50%), marked in 37 patients (39%), moderate in 8 patients (9%), and minor in 2 patients (2%). There was no persistent morbidity related to surgery. In patients with Parkinson's disease, the symptomatic improvement of tremor was rated as excellent in 51% of patients, marked in 36%, moderate in 11%, and minor in 2%. In patients with essential tremor, symptomatic outcome was classified as excellent in 57% of patients, marked in 36%, moderate in 5%, and minor in 2%. Six of the seven patients with kinetic tremor achieved marked symptomatic improvement, and one patient experienced moderate improvement. Forty patients experienced stimulation-related side effects. Side effects were mild in general, and they were reversible with a change in electrical parameters. They occurred more frequently in patients who had bilateral stimulation.

CONCLUSION

Excellent to marked improvement of tremor is achieved in the majority of patients with physiological target determination via implanted leads in thalamic deep brain stimulation. Interoperative test stimulation trials are unnecessary. Modifications in technique may help to reduce the costs of the related hospital stay.

Pregnancy is associated with low fear reactions in ewes

The aims of the study were: (1) to test the influence of pregnancy on responses of ewes to several fear-eliciting situations, (2) to compare the first and latest stages of pregnancy, and (3) to investigate possible correlations between fear reactions and progesterone levels. Fear reactions of nonpregnant (NP; N=22) and pregnant (P) Ile-de-France ewes (day 40 of pregnancy: N=43; day 140 of pregnancy: N=19) were compared during three situations classically reported to induce fear in sheep: isolation, surprise, and the presence of a human. P ewes displayed significantly lower fear reactions than NP ewes when isolated and when confronted with a surprise effect combined with the appearance of a novel object. This reduction in fearfulness may be mediated principally through reduced fear of isolation. However, fear of a human remained constant despite pregnancy. Fear reactions of ewes tested during isolation on gestation day 40 or 140 did not differ, suggesting that decreased fear is not restricted to the latest stage of pregnancy. A negative correlation was found between plasma progesterone levels and fear during isolation and surprise tests of ewes with low levels of progesterone. The decrease in fearfulness during pregnancy may have some adaptative value for the survival of the young.

Light irradiation increases embryotoxicity of photodynamic therapy sensitizers (5-aminolevulinic acid and protoporphyrin IX) in chick embryos

Photodynamic therapy (PDT) of malignant processes is based on the ability of a photosensitizer to first, accumulate in malignant (immature) tissue and second, to be destroyed following light irradiation. Because of the similarity between malignant and embryonic immature tissues, we investigated the deleterious effect of the PDT procedure on day 4 chick embryos in ovo. We compared experimentally the photodynamic effect (light-toxic) and the side effect (dark-toxic) of the clinically attractive photosensitizers 5-aminolevulinic acid (ALA) and protoporphyrin IX (PP IX). The dark and light embryotoxicity (i.e. lethality plus teratogenicity) was determined after intra-amniotic injection of one of a range of dose of each compound. Under dark conditions, PP IX exhibited embryotoxicity at a dose of 10 microg/embryo; however ALA did not exhibit embryotoxicity even at the highest dose (300 microg/embryo). Light irradiation of embryos following injection induced strong embryotoxic effects of both substances even at dark-ineffective doses.

Interactions of Neisseria gonorrhoeae with mature human macrophage opacity proteins influence production of proinflammatory cytokines

The pathological features of ascending gonococcal infection suggest that proinflammatory mediators secreted by tissue-resident macrophages are important components of the host response. Challenge of fully differentiated, mature macrophages with variants of Neisseria gonorrhoeae strain P9 or purified bacterial surface components (pili, lipooligosaccharide, and outer membrane vesicles) induced the secretion of interleukin 6 (IL-6), tumor necrosis factor alpha, growth-related protein alpha, macrophage inflammatory protein 1alpha (MIP-1alpha), and RANTES cytokines but had no effect on IL-8 production. No secretion of IL-1beta, epithelial-derived neutrophil attractant 78, granulocyte-macrophage colony-stimulating factor, IL-10, or IL-12 cytokines was observed. Notably, the P9-Opa(b) protein, in comparison to P9-Opa(a), increased the association of gonococci with macrophages and elevated the secretion of cytokines. Thus, variation in Opa protein expression by the gonococcus may be a determining factor in the severity of pelvic inflammatory disease.

Adenosine deaminase: functional implications and different classes of inhibitors

Adenosine deaminase (ADA) is an enzyme of the purine metabolism which catalyzes the irreversible deamination of adenosine and deoxyadenosine to inosine and deoxyinosine, respectively. This ubiquitous enzyme has been found in a wide variety of microorganisms, plants, and invertebrates. In addition, it is present in all mammalian cells that play a central role in the differentiation and maturation of the lymphoid system. However, despite a number of studies performed to date, the physiological role played by ADA in the different tissues is not clear. Inherited ADA deficiency causes severe combined immunodeficiency disease (ADA-SCID), in which both B-cell and T-cell development is impaired. ADA-SCID has been the first disorder to be treated by gene therapy, using polyethylene glycol-modified bovine ADA (PEG-ADA). Conversely, there are several diseases in which the level of ADA is above normal. A number of ADA inhibitors have been designed and synthesized, classified as ground-state and transition-state inhibitors. They may be used to mimic the genetic deficiency of the enzyme, in lymphoproliferative disorders or immunosuppressive therapy (i.e., in graft rejection), to potentiate the effect of antileukemic or antiviral nucleosides, and, together with adenosine kinase, to reduce breakdown of adenosine in inflammation, hypertension, and ischemic injury.

Receptor polymorphisms and diseases

The aim of our review is to summarize common genetic variations of some receptors associated with clinical consequences, which were not outlined in the previous special issue of this journal. Because of the multiple pathomechanisms of diseases, a set of genetic variation can play a role in the development of pathological conditions. From the data available three articles would merit a greater interest. In systemic lupus erythematosus the associations related to some polymorphisms of Fc-, tumor necrosis factor (TNF) alpha- and interferon receptor may explore new autoimmunological and inflammatorical pathomechanisms. In the endocrinology, the androgen receptor repeat polymorphism will exert significant aspects in the development of prostate cancer. The pleoitropic responsibility of vitamin D3 receptor polymorphism in the pathogenesis of immunological disorders (primary biliary cirrhosis, inflammatory bowel disease, type 1 diabetes mellitus) and of malignancies (malignant melanoma, breast cancer) shed light on the importance of common nuclear receptors. Nevertheless, in the future studies a more consistent approach minimizing requirement bias in the selection of patients will approve our understanding the role of genetic influence on the pathogenesis of diseases.

Radiological-pathological correlation: alveolar pattern

This review summarizes important pathological lesions of the lung that typically present radiographically with an 'alveolar pattern'. For each entity, the latest findings as to its pathogenesis, aetiology and pathology are reviewed in the introductory remarks. We then present the typical radiological appearances alongside macroscopic and microscopic pathological photographs. It is hoped that the parallel presentation of radiological image with the pathology will enhance the understanding of the diverse range of diseases the aevolar pattern comprises.

Imaging brain cholinergic activity with positron emission tomography: its role in the evaluation of cholinergic treatments in Alzheimer's dementia

One of the strategies in the treatment of Alzheimer's disease is the use of drugs that enhance cholinergic brain function, since it is believed that cholinergic dysfunction is one of the factors that contributes to cognitive deterioration. Positron emission tomography is a medical imaging method that can be used to measure the concentration, kinetics, and distribution of cholinergic-enhancing drugs directly in the human brain and assess the effects of the drugs at markers of cholinergic cell viability (vesicular transporters, acetylcholinesterase), at muscarininc and nicotinic receptors, at extracellular acetylcholine, at markers of brain function (glucose metabolism and blood flow), and on amyloid plaque burden in vivo in the brains of patients with Alzheimer's disease. In addition, these measures can be applied to assess the drugs' pharmacokinetic and pharmacodynamic properties in the human brain. Since the studies are done in living human subjects, positron emission tomography can evaluate the relationship between the drugs' biological, behavioral, and cognitive effects; monitor changes in brain function in response to chronic treatment; and determine if pharmacologic interventions are neuroprotective. Moreover, because positron emission tomography has the potential to identify Alzheimer's disease during early disease, it can be used to establish whether early interventions can prevent or delay further development.

Pediatric oncology in the third world

With 90% of world children living in developing countries and a rising cancer incidence, the third world bears the greatest burden of pediatric cancer. Pediatric cancers today are highly treatable, but 80% of children with malignancies die because they live in the developing countries where access to medical care is inadequate. Pediatric cancer care is expensive and available at only a few centers, which deal with excessive patient numbers and are staffed by inadequate numbers of physicians and nurses. There are marked geographic variations in incidences and presentations observed in the spectrum of pediatric malignancies. Initiatives to improve cancer care include setting up worldwide pediatric care units; establishing standard guidelines for treating patients; undertaking research and lobbying international organizations like the World Health Organization, United Nations Children's Emergency Fund (UNICEF), International Union Against Cancer (UICC), and the International Society of Pediatric Oncology (SIOP); to make chemotherapy, supportive care drugs, and opioids for palliation uniformly available. New outreach training programs would alleviate manpower shortages by linking centers from the two world regions for training and facilitate collaboration with international organizations.

Metastatic MHC class I-negative mouse cells derived by transformation with human papillomavirus type 16

In the endeavour to develop a model for studying gene therapy of cancers associated with human papillomaviruses (HPVs), mouse cells were transformed with the HPV type 16 (HPV16) and activated H-ras oncogenes. This was done by cotransfection of plasmid p16HHMo, carrying the HPV16 E6/E7 oncogenes, and plasmid pEJ6.6, carrying the gene coding for human H-ras oncoprotein activated by the G12V mutation, into secondary C57BL/6 mouse kidney cells. An oncogenic cell line, designated MK16/1/IIIABC, was derived. The epithelial origin of the cells was confirmed by their expression of cytokeratins. No MHC class I and class II molecules were detected on the surface of MK16/1/IIIABC cells. Spontaneous metastases were observed in lymphatic nodes and lungs after prolonged growth of MK16/1/IIIABC-induced subcutaneous tumours. Lethally irradiated MK16/1/IIIABC cells induced protection against challenge with 10(5) homologous cells, but not against a higher cell dose (5 x 10(5)). Plasmids p16HHMo and pEJ6.6 were also used for preventive immunization of mice. In comparison with a control group injected with pBR322, they exhibited moderate protection, in terms of prolonged survival, against MK16/1/IIIABC challenge (P < 0.03). These data suggest that MK16/1/IIIABC cells may serve as a model for studying immune reactions against HPV16-associated human tumours.

Is there a role for agonist gastrin-releasing peptide receptor radioligands in tumour imaging?

Gastrin-releasing peptide (GRP) has been shown to be a tumour growth stimulating agent for a number of normal and human cancer cell lines. The tumour growth effect is a direct result of GRP binding to membrane G-protein coupled GRP receptors (GRP-R) on the cell surface. Available data on the role of GRP and GRP-R in human lung, prostate, breast, colorectal and gastric carcinoma are reviewed and it is suggested that radiolabelled agonists are preferable to antagonists for imaging and therapy as they appear to be internalised, yielding a higher target/background ratio. The use of rhenium or indium radiolabels for therapy may provide a new approach to GRP/bombesin expressing tumours.

Major hematologic diseases in the developing world- new aspects of diagnosis and management of thalassemia, malarial anemia, and acute leukemia

The three presentations in this session encompass clinical, pathophysiological and therapeutic aspects of hematologic diseases which impact most heavily on developing world countries. Dr. Victor Gordeuk discusses new insights regarding the multi-faceted pathogenesis of anemia in the complicated malaria occurring in Africa. He describes recent investigations indicating the possible contribution of immune dysregulation to this serious complication and the implications of these findings for disease management. Dr. Surapol Issaragrisil and colleagues describe epidemiologic and clinical characteristics of the thalassemic syndromes. In addition to being considered a major health problem in Southeast Asia, the migration throughout the world of people from this region has caused the disease to have global impact. A unique thalassemia variant, Hb Ebeta-thalassemia, with distinctive clinical features, has particular relevance for this demographic issue. Special focus will be reported regarding recent prenatal molecular screening methods in Thailand which have proven useful for early disease detection and disease control strategies. Dr. Raul Ribeiro describes a clinical model for providing effective treatment for a complex malignancy (childhood acute lymphoblastic leukemia) in countries with limited resources. With the multidisciplinary approach in Central American of the joint venture between St. Jude Children's Research Hospital International Outreach Program and indigenous health care personnel, major therapeutic advances for this disease have been achieved. Given the major demographic population shifts occurring worldwide, these illnesses also have important clinical implications globally. These contributions demonstrate that lessons learned within countries of disease prevalence aid our understanding and management of a number of disorders prominently seen in developed countries. They will show how effective partnerships between hematologists in more and less developed nations may work together to produce important advances for treating major hematologic diseases in less developed regions. A major focus relates to the socio-economic and medical burden of these diseases in developing countries with limited resources. As such, these problems provide a challenge and an opportunity for collaborative interaction between hematologists and policy makers worldwide.

Statins in children: what do we know and what do we need to do?

Children have been tested and treated for hypercholesterolemia for more than 30 years. Although most treatment regimens have been limited to dietary intervention, statin use is increasing. Statins have been used in children since 1987, but published sources have only reported on small numbers of children with severe hypercholesterolemia. The available data indicates that statins can be useful and well tolerated. New data will be available in the next few years that will lead to the wider use of these drugs. Although statin drugs have proven to be safe in the adult population, physicians will be obliged to follow pediatric patients closely when these agents are widely used in the first few years. The use of highly effective safe drugs such as statins will allow for the assessment of the best time to initiate therapy in younger populations and what benefits may be found over the long term.

Persistence of Trypanosoma cruzi in chronic chagasic cardiopathy patients

BACKGROUND

Although patients with chronic chagasic cardiopathy do have a strong immune response against Trypanosoma cruzi, they have transient and low parasitemia as well as tissue amastigote nests. When conventional studies were carried out, demonstration of such abnormalities is minimally achieved. Molecular biology may provide the best tools to demonstrate parasite persistence, which could be pathogenic in this progressive disease.

METHODS

We studied 16 patients with chronic chagasic cardiopathy (CCC) at the Instituto Nacional de Cardiología Ignacio Chávez in Mexico City. Patients had undergone a complete clinical evaluation, and had antibodies against Trypanosoma cruzi. They came from different rural areas in Mexico. Blood samples were obtained and processed for hemoculture and PCR technique. A CCC necropsy case was also sought for the presence of parasite antigen or DNA, using immunohistochemistry and PCR methods in archival tissues.

RESULTS

Five of 16 (31%) hemocultures demonstrated circulating T. cruzi; 60% occurred in persons between 25 and 40 years old. In contrast, we found a positive PCR amplification in 81%; therefore, molecular biology tools appear to be more sensitive for demonstrating parasite persistence. There were no correlations between parasitemic state and clinical findings or specific antibody titer. The autopsy case had parasite antigens and DNA in heart tissues.

CONCLUSIONS

Chronic chagasic cardiopathy patients do have persistence of parasite even when parasitemia is low or absent. The continuous presence of a parasite load could maintain immune stimulus and perhaps enhance a pathogenic immune or autoimmune tissue damage in susceptible hosts.

Cytokines and other important inflammatory mediators in gestation and bacterial intraamniotic infections

Intraamniotic infections caused by viruses, bacteria or mycoplasmas are frequently followed by damage of fetus or increased perinatal morbidity and mortality. Cytokines are key substances regulating a number of biological processes including reproductive and inflammatory processes. An association between intraamniotic infections, rising concentrations of inflammatory cytokines in amniotic fluid and preterm labor is suggested. A great effort is made to find reliable markers typical for intraamniotic infections with high predictive value that make possible prompt identification of patients with intraamniotic infection. This review concerns inflammatory mediators, especially IL-1, IL-6, IL-8, TNF-alpha, and other important biologically active substances as prostaglandins and NO metabolites and their roles in intraamniotic infections. Finally, we discuss their relevance for diagnosis of intraamniotic infections.

Molecular determinants of non-specific recognition of delta, mu, and kappa opioid receptors

Identification of the molecular determinants of recognition common to all three opioid receptors embedded in a single three-dimensional (3D) non-specific recognition pharmacophore has been carried out. The working hypothesis that underlies the computational study reported here is that ligands that bind with significant affinity to all three cloned opioid receptors, delta, mu, and kappa, but with different combinations of activation and inhibition properties at these receptors, could be promising behaviorally selective analgesics with diminished side effects. The study presented here represents the first step towards the rational design of such therapeutic agents. The common 3D pharmacophore developed for recognition of delta, mu, and kappa opioid receptors was based on the receptor affinities determined for 23 different opioid ligands that display no specificity for any of the receptor subtypes. The pharmacophore centers identified are a protonated amine, two hydrophobic groups, and the centroid of an aromatic group in a geometric arrangement common to all 23, non-specific, opioid ligands studied. Using this three-dimensional pharmacophore as a query for searching 3D structural databases, novel compounds potentially involved in non-specific recognition of delta, mu, and kappa opioid receptors were retrieved. These compounds can be valuable candidates for novel behaviorally selective analgesics with diminished or no side effects, and thus with potential therapeutic usefulness.

Current trends in community-acquired methicillin-resistant Staphylococcus aureus at a tertiary care pediatric facility

BACKGROUND

The prevalence of community-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections increased at the University of Chicago Children's Hospital (UCCH) from 10 per 100,000 admissions from 1988 to 1990 to 259 per 100,000 admissions from 1993 to 1995. Because this increase may have represented a one time occurrence or a limited disease outbreak, we updated our previous observations at UCCH in 1998 and 1999 to see whether this trend had continued.

DESIGN

Prospective observational study.

RESULTS

Twenty-three hospitalized children had an MRSA isolate during the 1-year study period. Ten were community-acquired, equally distributed between children with predisposing risk factors and those without. The overall prevalence of community-acquired MRSA was 208 per 100,000 admissions. Seven of the 10 community-acquired MRSA isolates were susceptible to clindamycin. Skin and soft tissue infections predominated among the children with a community-acquired MRSA isolate. Pulsed field gel electrophoresis of the 10 community-acquired MRSA isolates revealed 8 distinct patterns; these data suggest that multiple clones were circulating at UCCH.

CONCLUSION

MRSA are no longer confined to children with established risk factors. The prevalence of community-acquired MRSA among children without identified risk factors is high in our institution.

"Café-au-lait spots" caused by vitiligo in McCune-Albright syndrome

Café-au-lait spots, fibrous dysplasia of bone, and endocrine gland hyperactivity are the principal features of McCune-Albright syndrome (MAS). Café-au-lait spots appear at, or soon after, birth. We illustrate "café-au-lait spots" acquired during middle age in a patient with MAS that are an illusion caused by vitiligo. This 64-year-old woman is the oldest patient reported with this disorder.

Effect of oral contraceptive steroid hormones on metabolic parameters of streptozotocin-induced diabetic rat

This study examined the effect of 0.05 mg norgestrel + 0.01 ethinyl estradiol (NEE) Kg x body wt(-1) on body weight, random blood glucose, glycosylated hemoglobin, and plasma insulin levels in streptozotocin-induced diabetic rats. Weight loss, blood glucose, glycosylated hemoglobin, and plasma insulin values of rats treated with NEE before and after the onset of diabetes were not significantly different from that of untreated diabetic rats. In conclusion, oral administration of these contraceptive steroid hormones does not significantly alter the metabolic parameters of diabetic rats.

Taenia solium disease in humans and pigs: an ancient parasitosis disease rooted in developing countries and emerging as a major health problem of global dimensions

This article reviews current knowledge on human and porcine cysticercosis caused by Taenia solium. It highlights the conditions favorable for its prevalence and transmission, as well as current trends in research on its natural history, epidemiology, immunopathology, diagnosis, treatment and prevention. Our opinions on the most urgent needs for further research are also presented.

Vasopressin receptors

The biological effects of arginine vasopressin (AVP) are mediated by three receptor subtypes: the V1a and V1b receptors that activate phospholipases via Gq/11, and the V2 receptor that activates adenylyl cyclase by interacting with Gs. Isolation of the cDNAs encoding the V1a and V1b receptor subtypes explained the tissue variability of V1 antagonist binding, whereas identification of the cDNA and gene encoding the V2 receptor provided the information to identify the mutations responsible for X-linked nephrogenic diabetes insipidus. Mutations that abrogate the production and/or release of AVP from the pituitary have diabetes insipidus as their most dramatic manifestation, indicating that the maintenance of water homeostasis is the most important physiological role of this neuropeptide. Evidence for a significant role of AVP in blood pressure control, although actively sought, has been scant.

Review article: potential therapeutic applications and mechanisms of action of heparin in inflammatory bowel disease

Unfractioned heparin was recently reported to be beneficial in the treatment of inflammatory bowel disease. The available uncontrolled data show that it may be effective in steroid-resistant ulcerative colitis with a percentage of complete clinical remission of over 70% after an average of 4-6 weeks of therapy. The administration of unfractioned heparin is not currently justified by the very limited available data. The worsening of rectal bleeding is infrequent in treated ulcerative colitis patients and only rarely does it require blood transfusion or a colectomy. Low molecular weight heparin was used in a single trial in patients with steroid-refractory ulcerative colitis, with results similar to those observed with unfractioned heparin. Since a prothrombotic state has been described in inflammatory bowel disease, and microvascular intestinal occlusion seems to play a role in the pathogenesis of inflammatory bowel disease, it is reasonable that part of the beneficial effects of unfractioned heparin in inflammatory bowel disease may result from its anticoagulant properties. However, beyond its well-known anticoagulant activity, unfractioned heparin also exhibits a broad spectrum of immunomodulating and anti-inflammatory properties, by inhibiting the recruitment of neutrophils and reducing pro-inflammatory cytokines. Moreover, it can restore the high-affinity receptor binding of basic fibroblast growth factor and this would aid healing of the ulcerated mucosa. In conclusion, unfractioned heparin may represent a safe therapeutic option for severe, steroid-resistant ulcerative colitis, although randomized, controlled trials are needed to confirm these data.