Quintuple Procedure for Ocular Surface Reconstruction and Visual Rehabilitation

PURPOSE

The aim of this study was to describe a combined surgical approach for ocular surface and visual rehabilitation in patients with limbal stem cell deficiency, corneal scarring, and cataract. We aimed to introduce this combined approach as an alternative to a staged approach and to describe the intraoperative use of a diamond ophthalmic burr (DOB) and optical coherence tomography (OCT) to achieve and confirm a smooth graft-host interface during the anterior lamellar keratoplasty (ALK) portion of the procedure.

METHODS

The quintuple procedure described herein consists of a modified ALK, cataract extraction, intraocular lens implantation, simple limbal epithelial transplantation, and temporal tarsorrhaphy. Intraoperative OCT and DOB were used to guide the creation of the stromal bed during the ALK. The procedure was performed in a patient with limbal stem cell deficiency and corneal scarring after a chemical ocular burn.

RESULTS

The tarsorrhaphy was removed at 3 months postoperatively once complete corneal epithelialization was observed. The best-corrected visual acuity improved from light perception preoperatively to 20/30 at 16 months postoperatively with the use of scleral contact lenses. At this postoperative time point, the cornea was clear and compact, and the ocular surface was stable.

CONCLUSIONS

The quintuple procedure allowed for visual and ocular surface rehabilitation in cases in which follow-up for a staged approach was not possible. Intraoperative OCT allowed for real-time visualization and dissection of the stromal bed, whereas the use of the DOB helped achieve a smooth stromal surface for an optimal graft-host interface.

Infectious and Noninfectious Corneal Ulcers in Ocular Graft-Versus-Host Disease: Epidemiology, Clinical Characteristics, and Outcomes

PURPOSE

To evaluate the incidence, clinical characteristics, microbiological profile, and therapeutic outcomes of corneal ulcers in individuals with chronic ocular graft-vs-host disease (coGVHD).

DESIGN

Retrospective clinical cohort study.

METHODS

Review of individuals diagnosed with coGVHD following hematopoietic stem cell transplantation (HSCT) who were seen at the Bascom Palmer Eye Institute between May 2010 and November 2021. Baseline demographics, clinical characteristics, microbiological profile, risk factors for corneal ulceration, and treatment outcomes were collected. Etiology was deemed infectious in individuals with a positive culture or appropriate clinical scenario (presence of stromal infiltrate or hypopyon); otherwise, ulcers were presumed to be noninfectious. Treatment success was defined as reepithelialization with infiltrate resolution, and treatment failure as progression to corneal perforation or keratoplasty. Kaplan-Meier survival analysis estimated the incidence of ulceration. Cox regression analyses examined demographic and risk factors. Infectious and noninfectious ulcer groups were compared using 2-way independent t tests, 1-way analysis of variances, and χ2 tests, as appropriate.

RESULTS

173 individuals were included (53.7±14.4 years old; 59.0% male). Thirty-three individuals developed an ulcer 74.5±54.3 months after HSCT, with estimated 5- and 10-year incidences of 14% and 30%, respectively. Twenty-two (66.6%) ulcers were deemed infectious (15 microbiologically confirmed, 7 clinically) and 11 (33.3%) were deemed noninfectious. Risk factors for corneal ulceration included Black race (hazards ratio [HR] 2.89, 95% CI 1.30-6.42, P < .01), previous ocular surgery (HR 9.16, 95% CI 3.86-21.72, P < .01), eyelid margin abnormalities (HR 3.44, 95% CI 1.69-6.99, P < .01), and topical steroid use (HR 2.74, 95% CI 1.33-5.62, P < .01). Conversely, contact lens use reduced the risk of corneal ulceration (HR 0.29, 95% CI 0.13-0.66, P < .01). Infectious ulcers had a significantly higher frequency of treatment failure than noninfectious ulcers (57.1% vs 20.0%, P = .04).

CONCLUSION

Corneal ulceration is a potential complication of coGVHD, with several clinical features identified as risk factors. Infectious ulcers had worse outcomes than noninfectious ulcers.

Translation and validation of the Visual Function and Corneal Health Status (V-FUCHS) questionnaire into Spanish language

PURPOSE

To translate and validate the V-FUCHS questionnaire into Spanish in a population of patients with Fuchs endothelial dystrophy (DEF).

METHODS

The V-FUCHS consists of 15 short, easily understandable questions that assess visual aspects of quality of life in patients with DEF, which can be gathered into a group of seven that assess the "Visual Difficulty" factor and another group of eight that assess the "Glare Factor". For the translation and cultural adaptation, the standardized norms for this process were followed, among other phases, a translation, a back-translation and an application in patients with DEF.

RESULTS

In the first phase, consensus was reached on the Spanish translation of the V-FUCHS. Subsequently, 25 patients were included to carry out the pre-test phase with the aim of assessing the applicability and feasibility of the test. The score obtained a minimum value of -0.88 and a maximum value of +2.44, according to the Rasch probabilistic scale. The mean value obtained from the Visual Difficulty factor was 0.61 (±0.71), while the mean for the Glare Factor was 0.41 (±0.51).

CONCLUSION

The validation of the V-FUCHS questionnaire, after its translation and adaptation into Spanish, proved to be a useful tool for assessing the visual quality of patients with DEF. Patients with a more advanced stage of the disease presented a greater severity in the test result. Likewise, the Glare Factor (Glare) correlates better with the pachymetric increase than with the visual acuity of the patient.

Intraoperative OCT Angiography in Pediatric Patients with Persistent Fetal Vasculature

PURPOSE

To describe abnormalities of the optic nerve microvasculature in patients with persistent fetal vasculature (PFV) and their fellow eyes using OCT angiography (OCTA).

DESIGN

Cross-sectional study.

SUBJECTS

Fifty eyes of 25 patients with PFV who underwent prospective imaging using supine OCTA during examination under anesthesia at Bascom Palmer Eye Institute from March 1, 2019, to December 31, 2022.

METHODS

OCT angiography images of the optic nerve of the included patients were analyzed with a primary focus on blood flow. Demographic, clinical, and treatment factors were compared with morphologic changes in the optic disc microvasculature.

MAIN OUTCOME MEASURES

Prevalence of optic nerve microvascular abnormalities on OCTA in the affected and fellow eyes of patients with PFV.

RESULTS

A total of 50 eyes from 25 patients were reviewed, and 28% (7/25) met image quality criteria for OCTA analysis. Optic nerve OCTA showed a persistent hyaloid artery (PHA) in all (7/7) PFV eyes analyzed. Of these, flow on OCTA was detectable in 57% (4/7). A Bergmeister papilla was evident in 100% (25/25) fellow eyes, of which flow was detected in 68% (17/25). Fluorescein angiography (FA) demonstrated blood flow within the stalk in 40% (10/25) of PFV eyes and within the Bergmeister papilla in 25% (6/25) of fellow eyes. Similar findings of abnormal blood flow and presence of fibrovascular stalk were seen in both treatment-naïve and treated groups.

CONCLUSIONS

OCT angiography allows for high-resolution visualization of subtle vascular abnormalities that are not readily apparent using RetCam FA and may serve as a useful noninvasive test to confirm the patency of the PHA and Bergmeister papilla in children. The results of the present study suggest that PFV may be a bilateral and asymmetric process.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Patients With Dragged Optic Disc Vessels and Retinal Folds: Clinical Features, Multimodal Imaging, and Histopathology

BACKGROUND AND OBJECTIVE

To describe the multimodal imaging and histopathological features of patients with dragged optic disc vessels (DODV).

PATIENTS AND METHODS

This is a retrospective, observational analysis using multimodal imaging of eyes with DODV in patients with retinal vascular diseases including familial exudative vitreoretinopathy, inflammatory disease, and others. In addition, two additional enucleated eyes with DODV underwent histopathological analysis.

RESULTS

Of the 13 patients, eight were girls and five were boys. Mean age was 5 years (ranging from 4 months to 10 years old). Of the 15 eyes, 12 (80%) demonstrated temporal dragging and three (20%) had nasal dragging. Retinal vascular abnormalities were present in 11 of the fellow eyes. Multimodal imaging demonstrated features of DODV including direction of traction, outer retinal thickening, increased flow, and other features. Only two (13.3%) eyes required surgical intervention. Mean follow-up was 14 (range 3 to 30 months) months. At last follow-up all eyes remained stable. Last visual acuity ranged from 20/100 to counting fingers. As well, two enucleated globes of adults with retinopathy of prematurity underwent histopathologic evaluation, showing optic nerve fibers that extended from the optic nerve into the DODV.

CONCLUSIONS

DODV is a sign of various late-stage retinal vascular diseases, associated with poor visual function. Multimodal imaging and histopathology can assist in understanding the disease pathology. [Ophthalmic Surg Lasers Imaging Retina 2023;54:634-642.].

Long-Term Comprehensive Management of Bilateral Limbal Stem Cell Deficiency Secondary to Severe Chemical Burn: 10 Years of Follow-Up

PURPOSE

To describe the long-term management of bilateral limbal stem cell deficiency secondary to a severe chemical burn.

METHODS

Descriptive case report.

IMPORTANCE

This case highlights the importance of early intervention in ocular chemical burns for the preservation of tissue integrity and avoidance of perforation. We also review the use of proper ocular surface reconstructive techniques to restore the function of the limbal area, as well as the immunomodulatory strategies and follow-up needed for these interventions.

The spectrum of COVID-19-associated chorioretinal vasculopathy

Purpose

Although conjunctivitis represents the most common ocular manifestation of COVID-19 infection, sight-threatening retinal involvement has been reported. Herein, we report and characterize with multimodal retinal imaging 5 cases of acute vision loss secondary to presumed chorioretinal vasculopathy temporally associated with COVID-19 infection with varying severity, visual morbidity, and treatment response, and review the available literature on the association between COVID-19 infection and retinal microvascular changes.

Design

Observational case series and literature review.

Methods

Multicenter case series of 5 patients who presented to academic centers and private offices with acute vision loss temporally associated with COVID-19 infection. A review of the literature was conducted using online databases.

Results

10 eyes of 5 patients, 3 men and 2 women, with a mean age of 30.8 years (median 33, range 16-44) were described. All patients had a recently preceding episode of COVID-19, with symptomatology ranging from mild infection to life-threatening encephalopathy. Treatment for their retinal disease included topical, oral, intravitreal, and intravenous steroids, steroid-sparing immunosuppression, retinal photocoagulation, antivirals, and antiplatelet and anticoagulant agents. Treatment response and visual recovery ranged from complete recovery of baseline acuity to permanent vision loss and need for chronic immunosuppression.

Conclusions and Importance

Clinicians should be mindful of the potential for vision-threatening retinal involvement after COVID-19 infection. If found, treatment with both anti-inflammatory therapy and anticoagulation should be considered, in addition to close monitoring, as some patients with this spectrum of disease may require chronic immune suppression and/or anti-VEGF therapy.

Gorlin Syndrome Associated With a Solitary Circumscribed Retinal Astrocytic Proliferation in a Pediatric Patient

Gorlin syndrome is a rare autosomal dominant disorder with near complete penetrance. The underlying genetic mechanism is a mutation in a tumor suppressor gene. Thus far, mutations in patched homolog 1 and 2 genes (PTCH1 and PTCH2) and the suppressor of fused gene (SUFU) have been identified. The syndrome is characterized by neoplasms arising early in childhood as well as developmental abnormalities, including ophthalmic anomalies. We present the first case associating Gorlin syndrome with a rare retinal lesion known as solitary circumscribed retinal astrocytic proliferation (SCRAP). SCRAP is a benign, stable retinal tumor. For this reason, it is essential to differentiate it from similar retinal lesions that are associated with poor prognosis. [Ophthalmic Surg Lasers Imaging Retina 2022;53:514-516.].

Role of corneal biopsy in the management of infectious keratitis

PURPOSE OF REVIEW

The aim of this study was to review the existing literature and investigate the role of microbiologic culture and histopathologic examination of corneal biopsies in the management of infectious keratitis.

RECENT FINDINGS

Corneal biopsy continues to be a significantly useful tool in the diagnosis and tailored management of infectious keratitis. Several techniques can be employed for tissue collection, handling and processing to optimize diagnostic yield and maximize safety, including emerging femtosecond laser-assisted biopsy.

SUMMARY

Corneal opacities represent a significant cause of global blindness, and infectious keratitis is the most common cause. Organism identification in progressive infectious keratitis is essential for proper management. However, microbiological culture alone has a high rate of false-negative results. Records from the Bascom Palmer Eye Institute were retrospectively searched for patients between 1 January 2015, and 31 December 2019, who underwent corneal biopsy, therapeutic keratoplasty or endothelial graft removal for infectious keratitis and had specimens bisected and submitted for evaluation with both microbiologic culture and histopathologic examination. Detection of bacteria, fungus and mycobacteria was not statistically different between culture and histopathology. Microbiology and histopathology are complementary methods for the identification of causative microorganisms in corneal specimens with presumed infectious keratitis.

Coats plus in prematurity

BACKGROUND

Coats plus syndrome or cerebroretinal microangiopathy with calcifications and cysts (CMCC) is an exceedingly rare autosomal recessive disorder that predominantly affects the microvasculature in the retina, brain, bones, and gastrointestinal system. Unlike Coats disease, CMCC is bilateral and affects multiple organ systems.

MATERIALS AND METHODS

Case report.

RESULTS

We report the case of two brothers with Coats Plus syndrome who presented with variable phenotypic expression. One sibling (Patient 1) was thought to have atypical retinopathy of prematurity and was only diagnosed with Coats plus after his older brother (Patient 2) presented with a seizure and a left upper extremity tremor at 4 years of age. The CTC1 mutation was confirmed in both patients. Aggressive treatment with laser photocoagulation and intravitreal bevacizumab dramatically improved the retinal vascular and exudative changes.

CONCLUSION

Coats Plus syndrome can have a variable phenotypic presentation, including retinal vascular findings. This rare genetic disease should be in the differential diagnosis in patients who present with atypical retinal pathology, including Retinopathy of Prematurity, Familial Exudative Vitreoretinopathy, or Coats disease associated with non-specific multiorgan abnormalities.

Peer-Assisted Learning (PAL): Perceptions and Wellness of First-Year Medical Students

INTRODUCTION

Medical education is oftentimes stressful and has been documented to compromise student well-being, hinder performance, and contribute to burnout. Many medical schools aim to foster students' sense of well-being. This can be accomplished by peer-assisted learning (PAL), which has the potential to improve student wellness and performance in medical school.

METHODS

The PAL program at Nova Southeastern University Dr. Kiran C. Patel College of Allopathic Medicine provides first-year medical students with educational sessions related to their curriculum, led by second-year medical students. The goal of this study was to determine the efficacy of PAL in promoting wellness and enhancing knowledge. Pre- and post-program surveys were distributed to students prior to and after the completion of PAL. Data analysis included frequencies of responses, qualitative analysis, and chi-square analysis.

RESULTS

Thirty-eight out of 51 first-year medical students responded to the pre-program survey (response rate 75%) and 23 out of 51 responded to the post-program survey (response rate 45%). A majority of respondents from the pre-survey believed that PAL would provide them with tools necessary to be successful. These findings were similar in the post-program survey with a majority of attendees sharing that PAL enhanced their knowledge, reduced test-taking anxiety, and provided useful skills.

DISCUSSION

Results from the pre- and post-program surveys suggest that PAL can enhance student well-being while improving knowledge of the material taught in medical school.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s40670-021-01381-0.

Behavior of Beta 2-microglobulin (B2-m) serum levels in uremic patients

This Study Was Performed In 97 Hemodialysis Patients (85 On Hd And 12 On Capd) To Investigate The Possible Correlation Between B2-M And Hemodialysis-Related Amyloidosis Syndromes (Hra-S); Differences In B2-M And Hra Behavior Between Patients Hemodialysed With Cellulose And Synthetic Membranes Were Also Included In The Present Study. Data Indicate That B2-M Levels Are Not Correlated With Dialysis Length Or With The Type Of Membrane Used For The Dialysis. On The Contrary, In 16 Patients With The Carpal Tunnel Syndrome, A Significant Correlation Was Found Between The Cts, The Dialysis Length And The Type Of Membrane (Greater Incidence With Cellulosic Membranes).

Leaching and Corrosion of Polyvinyl Chloride (PVC) Tubes in a Dialysis Water Distribution System

PVC tubes, from the dialysis water distribution system of a 14 and a 7 year old plant, were analysed by scanner electron microscopy (SEM) and X-ray microanalysis (EDAX). Results showed that the leaching of material occurs depending on time of use. The phenomenon does not modify the chemical composition of the material. Results suggest that PVC alterations, induced by time, could support bacterial proliferation thus reducing the quality of dialysate.

Chemical and biological characterization of dissolved organic matter from silver fir and beech forest soils

Despite a growing attention to the dissolved organic matter (DOM) in terrestrial ecosystems and evidence of the fact that vegetation affects the quality of both undissolved and dissolved organic matter in soil, the role of DOM as a biological indicator is still poorly understood. In this work, the fertility of 59 sites, divided into eight key alliances of the order Fagetalia sylvaticae Pawl., was studied considering chemical and biological parameters such as soil DOM, hormone-like activity, low-molecular-weight (LMW) aliphatic and phenolic acids, and floristic data. Both non-parametric tests and principal component analysis (PCA) revealed differences between silver fir and beech forests and within each type of forest. There were also differences between neutrophilous and acidophilous types. What's more, PCA reveals the dominance of the auxin (IAA)-like activity, and of some phenolic acids in distinguishing the acidophilous beeches (ACI) form the other types, whereas the gibberellin (GA)-like activity is more relevant in neutrophilous conditions such as thermophilous (THE) and mesophilous (MESO) beeches and montane (MO), high montane (HMA), high montane (HMC) silver fir forests. The GA-like activity is also related to the succinic, fumaric, malonic, and l-malic acids in the MO, HMA and HMC silver fir forests. Moreover, the role of LMW aliphatic acids in mobilizing the hormone-like activity, which improves forest growth, is stressed. The growth of seedlings of Picea abies was influenced by the phenolic acid content. At concentrations between 1 and 100 microM, phenylacetic and protocatechuic acids inhibited root growth to the same extent as indoleacetic acid, while p-hydroxybenzoic acid had a stimulating effect comparable to that of gibberellic acid. The aliphatic and phenolic acids appear to be related to plant strategies that influence soil fertility affecting plant growth through rhizodeposition. The role of LMW aliphatic and phenolic acids as molecular markers of ecosystem function is noted.

[Echo-Doppler in chronic kidney transplant rejection. The diagnostic prospects using indices of the ascending systolic phase]

To date, Doppler US has been rarely used to diagnose chronic renal transplant rejection because of its low sensitivity. Nevertheless, all the results have been obtained from the analysis of flow-metric indices, mainly considering the diastolic phase of the Doppler waveform, e.g., the resistance index (RI) and the pulsatility index (PI). This study was aimed at investigating if Doppler diagnostic accuracy in renal transplant monitoring can be increased by studying the systolic phase, considering peak arterial systolic velocity (Vp), acceleration time (AT) and acceleration index (AI). Seventy-six renal transplant recipients were examined with color-Doppler and duplex Doppler US, which showed 47 well-functioning and 29 hypofunctioning kidneys. The diagnosis was confirmed with perfusion scintigraphy with 99mTc DTPA, biopsy and 6-month clinical-laboratory follow-up. The means of Vp, AI, AT and RI relative to the group of patients with normal renal function were compared with those in the group of patients with chronic rejection. Critical values were measured at the segmental arteries (Vp = 70 cm/s, AI = 7 m/s2, AT = 100 ms), at the interlobar arteries (Vp = 45 cm/s, AI = 4 m/s2, AT = 100 ms) and at the arcuate arteries (Vp = 35 cm/s, AI = 3 m/s2, AT = 100 ms). On the basis of these values, normal functioning transplants were differentiated from hypofunctioning ones. RIs were altered (> 0.75) in 8 of 17 chronic rejections and in 3 of 47 normal transplants, with 47.1% sensitivity and 93.6% specificity. The combination of RI with Vp and AI strongly increased both sensitivity (100%) and specificity (82.98%). Combined AI and RI exhibited 94.1% sensitivity and 89.3% specificity. In conclusion, the indices of the ascending systolic phase, in peripheral vascular samplings, are clearly more efficacious than RI alone and index combination exhibits the highest diagnostic accuracy.

Leaching and corrosion of polyvinyl chloride (PVC) tubes in a dialysis water distribution system

PVC tubes, from the dialysis water distribution system of a 14 and a 7 year old plant, were analysed by scanner electron microscopy (SEM) and X-ray microanalysis (EDAX). Results showed that the leaching of material occurs depending on time of use. The phenomenon does not modify the chemical composition of the material. Results suggest that PVC alterations, induced by time, could support bacterial proliferation thus reducing the quality of dialysate.

Behavior of beta 2-microglobulin (B2-m) serum levels in uremic patients

This study was performed in 97 hemodialysis patients (85 on HD and 12 on CAPD) to investigate the possible correlation between B2-m and hemodialysis-related amyloidosis syndromes (HRA-S); differences in B2-m and HRA behavior between patients hemodialysed with cellulose and synthetic membranes were also included in the present study. Data indicate that B2-m levels are not correlated with dialysis length or with the type of membrane used for the dialysis. On the contrary, in 16 patients with the Carpal Tunnel Syndrome, a significant correlation was found between the CTS, the dialysis length and the type of membrane (greater incidence with cellulosic membranes).

Does anemia correction by rHuEPO improve uremic cardiopathy?

The correction of renal anemia by recombinant human erythropoietin (rHuEPO) makes it possible to assess the effect of anemia on uremic cardiopathy (UC). So far, conflicting results have been reported. We studied 10 hemodialyzed patients aged (51 +/- 18 years, dialytic age 47 +/- 18 months) before and after rHuEPO treatment. All patients underwent an echocardiogram before, and six months after stable hematocrit (31 +/- 2) was obtained. The results show a reduction in LVDD. No improvement in ejection fraction and in ventricular hypertrophy was observed, probably owing to an increase in blood pressure. Finally, there is a possibility that the myocardium of hemodialyzed patients undergoes anatomical changes which may not improve, even after anemia correction.

Epidemiology of viral hepatitis in dialysis centers: a national survey

Because of the great problem of viral hepatitis in hemodialysis patients, the Italian Society of Nephrology decided to perform a national epidemiologic survey. We contacted 467 nephrological centers by a questionnaire which let us have information on 25,746 uremic patients: 18,338 on HD, 2,250 on PD and 5,176 with kidney transplant, respectively 78.5% of the total Italian dialysed patients and 91.4% of the total transplanted patients. Statistical analyses were performed. HBV infections occur in 7.8% of the patients (2,008 cases) but considering that 485 cases became spontaneously negative, the true overall incidence of chronic carriers falls to 4.9%. The main causes of the infection are reported as transfusions (64.3%) and dialysis environment (12%). The vaccination program performed by 93.2% of the centers, obtained an efficacious seroconversion in 4,626 of 7,790 cases vaccinated: the vaccine currently most utilized is the recombinant type administered by means of 3 versus 4 boosters. In the 2nd part of the survey, we report information concerning the presence of nephropaties associated with HBV infections in nonuremic patients (208 cases). We present and discuss the clinical picture of the nephropaties, the hystologic bioptic pattern and the prognosis of the kidney pathology.

HBV infection in hemodialysis patients: monitoring and prevention

From 1986 to 91, 174 dialysis patients were studied. The prevalence of previous HBV infection and of chronic carriers was 33.3 and 4.6%, respectively. Immunization rate after vaccination (3 doses) was 63%. In 1991, we proposed a vaccination with 4 doses and recommend a 6-monthly anti-HBs evaluation to assess the timing of any booster dose needed.

Risk factors and clinical expression of HCV infection in hemodialysis patients

In our Dialytic Unit, the prevalence of antibodies to HCV (anti-HCV) was 16.4% in 1990 (73 hemodialyzed) and 21% in 1991 (105 hemodialyzed). The incidence of seroconversion was 13.1%. The transaminase behavior was similar in a group of anti-HCV-positive and a group of anti-HCV-negative patients and with previous HBV infection. Blood transfusions and dialytic age did not affect anti-HCV positivity.

LY 171555-induced catalepsy and defensive behavior in four strains of mice suggest the involvement of different D2 dopamine receptor systems

The D2 dopamine receptor agonist LY 171555 (0.5 to 5 mg/kg) induces dose-dependent catalepsy in C57BL/6, DBA/2 and BALB/c inbred strains of mice. This effect shows marked strain-dependent differences, since the response of C57BL/6 is significantly lower than those presented by the other two inbred strains at all doses tested. In previous studies we have shown that the D2 agonist at doses ranging from 0.5 to 5 mg/kg induces hyperdefensive responses toward nonaggressive opponents in mice of the C57BL/6 and BALB/c but not of the DBA/2 strain. Here we report that the outbred CD1 mice present both cataleptic and hyperdefensive responses when challenged with LY 171555. Forty-five percent of individuals presenting high defensive response and 11% high cataleptic scores. No correlation was found between catalepsy and hyperdefensiveness in CD1 mice following administration of 1 mg/kg of the D2 agonist. These results suggest that D2 receptor stimulation results in different behavioral responses, possibly mediated by different dopaminergic systems, depending on the genetic make up.

Sympathetic skin response in chronic renal failure and correlation with sensorimotor neuropathy

Twenty subjects suffering from chronic renal failure and undergoing continual treatment by haemodialysis were examined, and the following values assessed: maximum conduction velocity of the sensory and motor fibres of the common peroneal nerve, the relative electromyographic parameters, and the sympathetic skin response at the level of the foot. The results obtained have shown that autonomic neuropathy involving the sympathetic sudomotor is less frequent than sensorimotor neuropathy. The autonomic failures are scanty in the mild forms of sensorimotor neuropathy, with minor latency in the onset of uremia.

[Growth hormone after baclofen in normal and acromegalic subjects]

Serum growth hormone (GH) levels in basal conditions (two samples) and 30, 60, 90, 120, 150 and 180 minutes after oral administration of baclofen (20 mg) were evaluated in 6 healthy subjects and in 6 acromegalic patients. The effect of cimetidine (400 mg i.v.) administrated 45 minutes after baclofen (20 mg by mouth) were evaluated in 9 healthy women. Baclofen was able to significantly rise serum GH levels in normal subjects but no in acromegalic patients. Cimetidine suppress GH increase induced by baclofen. It was concluded that: 1) baclofen, GABAb receptor agonist, stimulate GH secretion by inhibition of GIF secretion or by stimulation of GRF secretion; 2) istamine, through H2 receptors in the hypothalamus, is important to mediate GH release induced by stimulation of GABAb receptors.

[Prolactin after baclofen in healthy subjects and prolactinoma patients]

Serum prolactin (PRL) levels in basal conditions (two samples) and 30, 60, 90, 120, 150 e 180 minutes after oral administration of baclofen (20 mg) were evaluated in 6 healthy subjects and in 10 patients with prolactinoma. The effect of baclofen (20 mg by mouth) on the PRL secretion cimetidine (400 mg i.v.) or domperidone (20 mg i.v.) induced were evaluated in 9 healthy women by administration of baclofen 60 minutes before cimetidine or domperidone. Baclofen was unable to significantly rise serum PRL levels in healthy subjects and in patients affected by prolactinoma and furthermore did not interfere with PRL rise domperidone induced. On the contrary baclofen decreased PRL rise cimetidine induced. It was concluded that: in basal condition, GABAb receptor don't play an obvious role in modulation of PRL secretion; when H2 istaminergic inhibition on PRL secretion is blocked (at an hypothalamic site), a GABA inhibition, b receptor mediated, on PRL secretion became more clear; the domperidone blockade of hypophysial dopaminergic receptors suggests that GABAb modulation of prolactin secretion don't obtain itself by dopaminergic pathways.

[Neurohypophyseal diabetes insipidus. Anatomo-clinical correlations]

Eighteen patients aged between 14 and 60 years suffering from diabetes insipidus were studied. Diabetes insipidus was diagnosed by means of Robertson's test. All patients underwent C.T. scanning and evaluation of PRL basally and after TRH (200 mcg e.v.). Twelve patients (66%) showed neurological lesions (secondary central diabetes insipidus). Six of these patients had hyperprolactinaemia. Our data suggest that most of central diabetes insipidus are associated with central system nervous (S.N.C.) damage. In same cases the presence of hyperprolactinaemia suggests a brain damage. Therefore neuroradiological study is very important in all cases of neurohypophyseal diabetes insipidus.

[Evaluation of TSH secretion after GnRh in patients with primary hypothyroidism]

6 women (mean age 38 years) with high Thyroid Stimulating Hormone (TSH) serum levels because affected from primary hypothyroidism were studied. 6 healthy women (mean age 31 years) represented the control group. All subjects underwent evaluation of serum TSH, Follicle Stimulating Hormone (FSH), Luteinizing Hormone (LH), basally and 20, 30, 60, 120 minutes after administration of Gonadotropin Releasing Hormone (GnRH: 100 meg. IV). Seric FSH and LH show a large increase 30 minutes after GnRH either in healthy or in hypothyroid subjects. TSH is unresponsive to GnRH in normal condition, while shows a clear decrease (-78%) 30 minutes after GnRH in primary hypothyroidism. Rarely the hypothalamic releasing hormones possess an inhibitory effect on anteipophyseal secretions. Previously a GnRH inhibitory effect on prolactin (PRL) release from PRL secreting tumors in rat. The GnRH inhibitory effect on TSH release in pathological conditions such as primary hypothyroidism is difficult to explain: it may be that GnRH acts on Central Nervous System or at pituitary level: in the last case it could bind sites which are not quite different in the different glycoprotein secreting cells.

[GH after baclofen and diazepam]

It has been proposed that GABAergic receptors possess two functionally distinct, but strictly co-operating binding sites, one for GABA itself, another for benzodiazepines. The activation of GABA receptor is followed by opening of the Cl- channels. This action is strengthened if both binding sites of GABA receptor are contemporaneously engaged by their respective agonists. Baclofen, a GABAergic drug, is able, in acute administration, to determine an increase of serum GH in man. The aim of this work was to control if benzodiazepines can strengthen this metabolic effect of Baclofen in vivo. Five healthy voluntary women were studied. Blood samples for serum GH evaluation were collected basally and 30, 60, 90, 120, 150, 180, 210 minutes after oral administration of 20 mg. of Baclofen. This test was repeated one week after oral administration of 12 mg. die of Diazepam. The results were analyzed for paired data. The finding show that the metabolic effect of Baclofen on GH secretion are prolonged in time after Diazepam premedication and suggest that GABA-benzodiazepines interaction is effective at hypothalamo-hypophyseal level in man.

[Plasma cortisol levels after acute administration of baclofen]

Plasma cortisol levels after acute administration of Baclofen, a Gaba agonist drug, were evaluated in eight healthy volunteer subjects. After 10 mg. of such drug, cortisol levels did not change appreciably. On the contrary after 20 mg. Baclofen elicited a rise in cortisol plasma levels. Baclofen increases striatal levels of dopamine. Therefore it is possible that metabolic effects of the drug are a consequence of increased levels of dopamine.

[Hypophyseal gonadotropins after GnRH in patients with hypophyseal tumors and after hypophysectomy]

The effects of GnRH administration on serum FSL and LH concentrations were evaluated in 6 patients with pituitary tumors before and after surgical ablative treatment. After surgical therapy LH is suppressed, while FSH concentrations are not statistically different before and after surgical procedure. These data suggest that FSH and LH may be controlled by two different physiological mechanisms of their secretion.

[Hypophyseal gonadotropins after GnRH in patients with pituitary tumors]

The effects of exogenous GnRH on plasma FSH and LH concentrations were evaluated in 12 patients with pituitary macroadenomas and in 11 patients with pituitary microadenomas. In patients of the former group the mean values of FSH were not increased as compared with healthy controls, while LH was significantly lower. In patients of the latter group FSH was strongly greater than in normal controls, while serum LH concentrations were included in the normal range. These findings suggest that the exaggerated response of FSH can be useful to the diagnosis of the pituitary microadenomas.